It is revealed that Maria in Hayate the Combat Butler is only 17, but she is incredibly mature and everybody mistakes her for a beautiful woman in her mid-to-late-20s, leading Hayate to believe that he likes older women. It also becomes a Running Gag that Maria is irritated when people mention "young girls" as if she doesn't fit into that group.
Specifically, she keeps saying "I'm 17-years-old" with increasing irritation. It's also a Shout-Out to Kikuko Inoue.
Mildly subverted in Bubblegum Crisis: given how long ago sexaroids were labeled as illegal by the series start, we get the implication that while Sylvie and Anri may not be as old as they look (Sylvie appears in her mid-twenties while Anri looks to be the loli model), they're not single digit ages.
Yagi Yuria in Shibatora works at a maid cafe, passing as over eighteen, but is really only twelve years old. The fact that her mental maturity is normal for her real age, not her appearance, results in her being exploited by a number of other characters.
Zelgadis the chimera of Slayers is 20 at the start of the Light Novel series, and his appearance appropriately matches his age. In the anime though, his age is bumped down to sixteen (a Word of God statement in a film book), making him fall under this trope. It doesn't help that his voice is noticably deep, especially in the English version. More often than not, Gourry (who's older and taller than Zelgadiss is; in the anime, he's the only protagonist who starts out in his twenties) is referred to as a boy.
In Excel♥Saga, a paedophile takes a nine-year-old to a love hotel, only to learn that she's, er, "prodigious"* meaning she was able to completely hide away her triple-g cup breasts. The episode in question was making as many jokes that couldn't be aired on TV as possible (it didn't, which was what the creators wanted), but everything was still played for laughs (all black laughs), which meant the paedophile left the under aged girl broken hearted when he saw what she looked like, before anything awful happened. Yep.
Well, when the episode is titled "Going Too Far", what did you expect?
Harumi in Irresponsible Captain Tylor appears to be in her mid-twenties, but viewers who have a quick enough eye to catch her character stats just before the commercial breaks will be surprised to realize that she's only 3 years old. It turns out that she's an android, so don't worry too much about it.
A more mundane example in the same show would be Dr. Kitaguchi, a 33 year-old doctor who looks like he's somewhere in his 50s. If his self-proclaimed thirty-year drinking habit isn't an exaggeration, you can probably figure out why.
Yu-Gi-Oh! GX has Professor Banner, who looks like he's in his mid-20's, but he's actually 18. It's because that at 18, he contracted a terminal disease while doing alchemy research, so he made a second body to continue research and stop the funder of his research, Kagemaru.
Yuki Nagato and her associates in Haruhi Suzumiya appear to be about fifteen, but as constructs of the Data Overmind, their physical bodies at least are only up to three years old. It's somewhat debatable since it isn't known how the whole system works, but with Nagato getting trapped in a time loop for hundreds of years (and mentally aging, as she alone retains full memories of the repetitions) the fifth novel inverts this and makes her Really 700 Years Old.
An alternate theory mentioned in the show is that the whole universe was recreated three years earlier, so * everyone* who thinks they're older than three is actually Younger than They Look.
Kyon's sister's friend Miyoko is this. She is the same age as his elementary school aged sister but appears to be within a year of Kyon's age.
Yoko in Tengen Toppa Gurren Lagann is actually 14, the same age as Simon. However, since humans had been living underground for generations, without a sun or anything, they probably couldn't tell time as accurately, so who knows. Although, supplementary material, such as the official anime guide, states that she is actually 18.
In Planetes, a minor character is twelve years old, but since she grew up on the Moon with it's lower gravity, her growth rate was accelerated and her size makes her look like she's in her early twenties. This causes the twenty-something main character to be really uncomfortable when he discovers her true age... especially since it appeared he'd been developing something of a crush on her.
In Mahou Sensei Negima!, two of the Huge Schoolgirls are forced to pay full price for movie tickets, even though they're only 14-15 years old (While two of their classmates who are a couple months older but look younger get away with claiming to be elementary school students for a larger discount). One of them gets so mad, she uses magic age-reducing pills to turn herself into a small child, until she realizes (too late) that the cost of the pills combined with the ticket come out to more than she would have had to pay normally. The other, being a Ninja, just Henges herself younger for free.
There's Chachamaru, who has been built two and a half years ago, but looks like a teenager.
There is also Naba Chizuru, who is explicitly the youngest girl in the class aside from the android but is maternal enough (in multiplesenses of the word) to pass for at least 20.
Jet of Cowboy Bebop looks like he could be in his forties or fifties, but is only thirty-six. This is lampshaded in the preview for "Waltz for Venus" where he tells us this, and says you shouldn't judge people by how they look, or how much hair they have.
Much of the cast of Eyeshield 21 qualifies, but the one that takes the cake is Rikiya Gaoh: He's two meters tall (6'7"), square-jawed, musclebound, capable of bench-pressing over 200 kg (over 440 lb)...and we're supposed to believe that he's a high school freshman. Some of the other characters don't believe it either ("There oughta be a law against players like him!").
That's not even getting into Atsushi Munakata of the Amino Cyborgs, whose tremendous musculature and broad, dashingly handsome face make him look over 30, a fact that is actually commented upon. One Omake chapter shows that he actually looks exactly like his father... and his mother.
Pictured above: Lampshaded when Sena and Monta discover the identity of Musashi, who they only knew as the middle-aged looking construction guy who worked on their ever expanding clubhouse. They cry out in unison "you're seventeen??!!"
Similar to Musashi, Yamabushi from Shinryuuji looks much older than he is due to his half-grown in beard. He's even charged with pumping up the Japanese youth cup team before the game against America because he looks the oldest. When he gets too emotional, the similarly adult-looking Mamoru Banba steps in to offer his own uplifting words.
Mr. Don, Gaoh's opponent in the American game, is supposed to be 18, but looks closer to sixty with his white hair, massive stature, and heavily-wrinkled face.
Lampshaded in a chapter where we learn they even have rankings for who has the worst case of "old man" face.
You would never, ever know it by looking at him or hearing him talk, but Piccolo at the beginning of Dragon Ball Z is chronologically only eight years old. Nobody remembers this, for good reason.
When he was born he was supposed to be a demon. He actually takes much longer to reach maturity than Piccolo Daimaou's other "offspring", who are full-grown when they hatch.
In a similar vein, Cell is much, much younger than you'd expect - even with all the time-traveling he had to do to reach a timeline where he could absorb the Androids, he's still only in his early twenties.
In Dragon Ball GT, there is an extreme case of this in the Shadow Dragons, who, though mature as any other Dragon Ball villains, are, by technicality, newborns, spawned from the dragonballs' misuse.
Trigun's main character Vash starts out in Younger than They Look form, seeing as he's really a plant-like alien who matures into a young child far more rapidly than a human would; when the series opens, however, he's Older than They Look, seeing as he's existed since before the incident that initially colonized the planet.
However, Wolfwood in the manga does have a Lampshaded case; The experimental treatments his Evil Mentor used to give him superhuman capabilities and Healing Factor also caused him to age faster; while he looks in his mid-to-late 20s, he's probably sixteen or so when we meet him. His former guardian at the orphanage doesn't recognize him until Livio's about to kill him.
Guts from Berserk because of extreme amount of physical and mental stress looks to be about 30 or 40. If you pay attention, you'll be surprised to learn that Guts is around 22.
Umehachi, male protagonist of the manga Tende Freeze, is 17, but looks like he should belong in junior high. (Admittedly, he regularly acts that age, too.) This is repeatedly lampshaded with people who get it wrong; his brother is in junior high but looks far more grownup than his brother (and, again, acts the part too...); when they go to the movies, they buy each other's tickets to avoid lengthy explanations.
While Satella of Chrono Crusade looks somewhere around her late twenties or early thirties, she turns out to only be nineteen years old much to the surprise of Rosette.
One of the students in Doki Doki School Hours looks and acts like a middle-aged man even though he's still in high school. They even call him "Oyaji" (i.e. "Geezer" or "Pops").
In Slam Dunk, Shinichi Maki, the captain of Kainan team, looks like he was over 35 but he is only 17. After learning it, Hanamichi immediately nicknames him "Middle-aged Man" and never calls him by his real name. Maki retaliates by pointing out that Akagi, Shohoku's captain, looks even older. And later on in the series, Uozumi (whose the same age as Akagi), is mistaken for Akagi's father.
Arf is another example. She looks to be in her mid twenties or so, but in reality is probably only three or four years old tops considering Fate created her, and Fate herself is a another example as a clone with a copy of the memories from the girl she was cloned from.
By extension, this trope applies to Erio and Zest for the same reasons as Fate.
Sette looks like an adult woman, but is the last of the Numbers to have been activated, and thus younger than any of the others (particularly Cinque, who is a direct inverse: looks like a kid, has the mind and skills of a seasoned commando).
Occurs with the all young girls in Junko Mizuno's Pure Trance manga; they appear to be about three when they're born, and one quickly ages about 16 years in a matter of months due to her ability to shed her skin like a snake.
The silpelits from Elfen Lied Age at about double the rate of normal humans. Nana looks 14-15 and is really around seven years old. Similarly, Mariko is really somewhere around three years old.
Teuchi, the ramen shop owner, appears to be in his 60s at best but is only 43 at the beginning of the manga. It's also implied Kakashi was 6 when he became a genin but he looks indistinguishable from even the current cast, who were 12 when they became genin.
Hana-chan in in the final season of Ojamajo Doremiafter she aged herself magically from a baby to a tween.
Primula from SHUFFLE! appears to be around eleven or twelve years of age. She's actually younger, since she's the most recent test subject of the Yggdrasil Project.
Isabella from Paradise Kiss is high school age, but dressing like a middle-aged Victorian lady makes her look remarkably older. Her very mature and composed attitude only add to it, as do her knobbly, slightly manly hands.
Otaku No Musume San: Taeko, a high school student who also happens to be a landlady, often is assumed to be a lady cosplaying as a high school student (mostly because the tenants are generally otakus themselves, so it's not a big leap). Amusingly, her mother actually works at a Cosplay Cafe and was mistaken for Taeko's friend when she turned up in her work uniform. The combination of the two tropes lead to Taeko looking older than her mother.
Ling Yao of Fullmetal Alchemist is a mild case. He's 15, but he looks like a fully-grown adult. This is used for both a joke about him being much taller than Ed (who is slightly older) and a plot point when he's arrested as an illegal immigrant and the authorities don't believe he's really a minor.
Hibiki no Mahou has Asuma, a wizard who ages much more quickly than normal as a price for using magic. In reality, he's probably at least in his late teens, but he looks to be about in his late 20's/early 30's.
In Neon Genesis Evangelion, it's implied that Rei is in fact a 4-year-old with the mind of a 14-year-old as a result of being a clone. On the other hand, there's no evidence the clones haven't been growing at a normal, human rate, so physically they could all be 14. It all depends on how you interpret what counts for age: mind, body, or soul? How much are Rei I, II, & III the same person?
Yukio Oikawa of Digimon Adventure 02 would be in his early thirties, but you'd never know that by looking at his grey skin and sunken eyes.
In Sailor Moon, when ChibiUsa and Hotaru are possessed, they take the forms of adult women, though they both are children younger than any of the other characters.
Pinoko of Black Jack depends on how you count it. She started life as a teratoma (a form of tumor) that had grown everything but a body while attached to an eighteen-year-old woman. If you count her life starting with her "sister", she's eighteen and Older than They Look; if, like Black Jack, you count her life from when she was removed, she's less than a year. Either way, her artificial body looks about six.
Stiyl Magnus. You know, this red-haired guy who's smoking all the time and is about two meters tall. Believe it or not, he's just 14.
This is actually a result of a miscommunication between the writer and the artist. The writer said that Stiyl's battle with Touma was meant to be "old vs new" meaning magic vs science. The artist read that, missed the note after about Stiyl's age, misinterpreted it to mean "old man vs young man" and drew Stiyl as a man in his 30s.
Kanzaki and Oriana also looks around 20-25 when they're both only 18.
All of the Misaka clones, naturally. Most noticeable with Worst, who looks older than the rest (including older than her original), but is actually the youngest clone. She is teased at one point that, despite looking 16, she's technically the "younger sister" of Last Order, who looks 10.
Misaki Shokuhou, the fifth level 5 esper, looks like a buxom college or high school girl, but is actually in middle school. However, since her power is Mind Control, it's theorized (both in-universe and out) that she is actually as old as she looks, but she's just shaving a few years off her age with her ability.
George of Dragon Crisis!, despite looking about thirty, actually turns out to be 19.
Honey Kisaragi passes for 16, but since she's actually the transforming android Cutey Honey, she was probably built more recently than that.
Gareki from Karneval looks in his early twenties but is actually only 15. He's only a little bit shorter than Yogi, who's 21, and he acts as a guardian/big brother to Nai which doesn't help.
Akagi: Shigeru is only 13 pre-Time Skip but looks considerably older in the anime (he's more plausible in the manga). A line referring to his age was even changed from "Yeah, you look it too" to "Really? You don't look it" in the adaptation.
Leorio from Hunter × Hunter looks like a businessman in his thirties or early forties. He's nineteen. It was even lampshaded when he tells Gon and Killua, who are more than shocked.
YuYu Hakusho has an early joke about this—a creepy one-shot youth gangster who kidnaps Keiko in the manga, who has an oversized head with overdeveloped bone structure and a load of stubble. In an early panel where he's perving on Keiko his face is labelled, 'fourteen years old.' I.e., in his last year of middle school.
Shinonome Nano from Nichijou looks and acts like a high schooler but she is actually only a year old at the beginning of the show. She's a robot (with a wind-up key, natch).
Miki Aono/Cure Berry from Fresh Pretty Cure!. She's a gorgeous aspiring model and quite tall, in fact, the tallest of the Fresh Cures and the second tallest overall Cure (only beaten out by Yuri Tsukikage/Cure Moonlight from HeartCatch Pretty Cure!, who's the oldest of all active Cures) also a former holder of the 'Babaa' nickname. High schooler, yes? Nope. She's 14.
Megumi of Servant × Service may look like a senior staff, but that's mainly out of the effect of her stoic demeanour. She's actually 20, in the same age of the youngest newcomer in her office.
Suzumura from Kami-sama ga Uso o Tsuku is an eleven year old elementary school student who towers over the other kids.
Noguchi from the Sangatsu No Lion, who is a highschooler despite sporting a thick mustache. Lampshaded in the first chapter he appears in with notes constantly pointing out that he's a 2nd-year.
In AKIRA when a Juvenile Corrections Officer is lecturing Kaneda and the gang on their behavior, Kaneda calls him "gramps" as an insult, the man tells him he's only 25, he appears to be in his mid 30's-early 40's.
Subverted in Kill la Kill - despite being a high-school senior, Ira Gamagoori doesn't look like he could realistically be in his teens... Because he isn't. It turns out that he deliberately put off leaving middle school for a couple of years so that he could be in the same year as (and thus serve under) Satsuki.
Mako: That explains the old-man face!
In Sankarea, Darin looks to be somewhere in her mid-20's to early-30's, but eventually lets slip that she's actually only 14. The other characters are so dumbfounded by this that they focus more on the fact that they're actually older than her than anything important she's telling them. Her older appearance was likely intentional on her part, but even after she relaxes her "mature" look somewhat, it's still very rare for her to actually look 14.
Magneto is old enough to have lived through the holocaust, but has been de-aged and re-aged back into his 20s/30s. You'd never expect he and Xavier are the same age.
Bart Allen (aka Impulse, then Kid Flash, then The Flash) in The DCU aged unusually quickly for the first few years of his life due to an exceptionally fast metabolism. The reverse is true for his Evil Twin Inertia, who took over 50 years to develop to the physical age of 15.
As indeed is Superboy (as in the Superman clone introduced in Return of Superman), who's presumably even now well under ten comic years old, but looks at least fifteen. He was supposed to look even older, as his growth was being accelerated to the point where he could replace the original Superman, but he was broken out before he was ready.
Victor Mancha of Runaways. He's a cyborg implanted with false memories. He was built as a teenager, so he's approximately 15 years younger than he looks. Molly even comments that she forgot that he's younger than her.
Representative Joshua Freeh, of Transmetropolitan, is the product of a "Bastard Farm" given a wetware upgrade so he has full higher brain functions, created so the Big Bad would have a running mate with a clean-slate past.
Spider Jerusalem:Josh Freeh was the perfect running mate. He had no skeletons in his closet. Hell, he's only two years old!
Both Captain Marvel and Mary Marvel, thanks to Older Alter Ego. Lampshaded in Formerly Known as the Justice League. At one point Captain Marvel had to break up with the teenaged superhero Stargirl because even though they were the same age, it just looked really creepy.
It used to be even more extreme; Billy and Mary had the exact same superhero forms when they were pre-teens. Though Comic Book Time makes this a very slow process, they're narrowing the age gap with their alter-egos. Given Black Adam's example, eventually they'll be Older than They Look, as their Captain Marvel and Mary Marvel forms don't age at all.
Like Billy and Mary, there's Colin Wilkes from Streets of Gotham. With the Venom in his sytem activated, he's as brawny as Bane and looks completely like an adult thug. He's a hero and around the same age as Damian Wayne, who he (sort-of) befriends.
Snowbird of Alpha Flight was a fully grown woman at the age of six.
Prime of Ultraforce is really a thirteen-year-old boy who takes on an adult appearance when powered up. Makes for some raised eyebrows when he proudly announces that the thirteen-year-old girl he has a crush on is his girlfriend.
Magik of New Mutants fame spent half her life in a realm of Limbo outside the normal timestream. As a result, she was a teenager despite technically being born 6 years prior to her abduction, much to the X-Men's shock, since seconds passed on Earth for them.
Jenny Quantum of The Authority looks about 14 or 15. Actually, she was born at the turn of the century - she was just really sick of being treated like the little kid she was, and had the reality-warping power to change that.
The children of Mother of Champions, of the DC Comics Chinese superhero team The Great Ten, age 10 years every day. Between this, the fact they all have Super Strength, and the fact Mother can produce a new batch every three days, they are considered cannon fodder of the finest kind.
Eisenstein, a minor-ish character in Preacher, has "looked over a hundred" since he was 12.
Marvel Comics hero Rage was about 14 when he started his superhero career, but looked like he was at least 30 due to his gargantuan size and muscles. Prior to getting his powers he looked like a regular kid. In any case, this gives him the distinction of being the youngest Avenger ever - so young that when the team discovered his true age they sent him to the New Warriors and told him to come back when he was 18.
When Helen goes on her first date with Atomic Robo in The Deadly Art of Science, she does not react well to the discovery that Robo is only seven years old.
Robo: Intellectually I'm twenty to twenty-five. It's not that bad.
Robo: Well, sometimes it helps to step away from a problem.
Helen: And sometimes you realize your boyfriend is eight years old.
Robo: Seven. But, hey! Now "robot" isn't the weirdest part of our relationship.
Master Splinter, the agedmentor of the Teenage Mutant Ninja Turtles, is younger than you'd think. Rats generally live less than three years (five is exceptional, and seven is the record). When the series begins (about fifteen years after his mutation) he'd still be less than twenty years old.
Taken even farther in the IDW comics, where the story begins only 18 months after their mutation, making them all less than 5-7 years old at the most. Justified in that Splinter, and the Turtles to a lesser extent, have some memories of a past life.
Skaar, The Hulk's son. Looks like an adult in Hulk form, a teenager when in 'human' form, but in actual fact is only a couple of years old, thanks in part to his mother being an alien with an accelerated aging rate. His twin, Hiro-Kala, looks like a young teen.
The Stepford Cuckoos are clones of Emma Frost who had been aged up from birth to their teens in order to infiltrate the X-Men. They're only a few years old chronologically.
Legacy of ch'Rihan: Morgan t'Thavrau is 49, which is barely middle-aged for the Vulcan-descended Romulans, but she looks a lot older from having spent 21 years working in field and vineyard.
The concept to Jack starring Robin Williams was about a boy that ages four times faster than normal, with him having the body of a 40 year old with the mental age of 10.
A deleted scene in Napoleon Dynamite has the mustachioed transfer student Pedro exploit this to buy a lottery ticket. Peluca, the short film on which Napoleon Dynamite is based, has this scene as part of its central plot. The lottery scratcher gives the characters just enough money to buy a wig for another character who had shaved his head.
The Island has clones that appear to be various ages, from thirties up to their sixties. It turns out that oldest ones are no more than four years old.
One horror example exists in Warlock, in which the title character curses the female protagonist to age 10 or 20 years for each night that passes. She remarks to Redfern, "This is worse than death", to which he replies, "That's what he had in mind."
Seeing Double had clones of S Club and various other celebrities that were artificially aged so they could take their places, but kept in a childlike state.
The clones are altered to grow twice as fast in order to be battle-ready sooner. The Star Wars Expanded Universe features a Jedi being confused because she senses a child in the Force, but sees a grown man.
In Episode III, the soon-to-be-Emperor Palpatine ages to about 110 in a matter of seconds (he was really 63). The Expanded Universe came up with the idea that it was his normal appearance (after years of Dark Side corruption), but he was disguised in some way, and the stress of his battle with Windu broke that beyond repair.
Padme in The Phantom Menace is a fourteen year old queen wears a lot of ceremonial makeup and elaborate costumes, apparently to disguise the fact that she's so young. Even still, she's actually the elected leader, so the people must be well aware of her age.
There was a point in the Clone Wars where some Separatists were cloning Nikto, presumably to supplement the droids. The facility was discovered and went under seige, and the cloners decided to respond by bumping up the growth rate to get as many new adults as possible. This didn't work out too well in the end.
The titular character of The Curious Case of Benjamin Button, who starts life looking as an old man and dies as a baby, so as a child looks like a small eighty-year-old. He even says to another character early in the movie, "Seven. But I look a lot olda."
J F Sebastian in Blade Runner is in his twenties, but he looks around fifty due to an aging disease (most likely Werner's syndrome). The Replicants are created as young adults and have a four year lifespan.
Tom Hanks's character in Big is a child in the body of an adult, thanks to a magic wishing machine.
In Catch Me If You Can, 16-year-old Frank Abagnale is played by 28-year-old Leonardo DiCaprio. This is justified by the fact that the real-life Abagnale also looked much older than he was, and in fact, his deceptive looks were a key part of how he was able to pull off his scams. After Agent Hanratty encounters him for the first time, he profiles Frank as someone being in his mid-to-late twenties.
Ree's mother in Winter's Bone. She's probably in her late 30's but looks more like 60.
Trainspotting: Mark Renton meets Diane in a club, then goes to her house where they have sex. Immediately after the act she kicks him out of her room and he sleeps on a sofa. In the morning it's revealed that she's underage. She even threatens to report him for sex with a minor if he doesn't see her again.
Peter Selleck (Rob Riggle) from The Goods, who is stated to be 10, despite looking like he's in his forties.
In Brave New World this is mentioned as an attempt to create lower-caste proletarian workers who efficiently skip all those useless developmental years, but the six-year-old men and women are too mentally under-developed, and the program fails.
Somewhat subverted in The Catcher in the Rye. Holden Caulfield's hair is starting to grey on one side as a teenager, and he claims several times that it makes him look more mature than he is, but hardly anyone is fooled when he tries to pass for older.
Wilbur Whateley of H.P. Lovecraft's The Dunwich Horror grew unnaturally quickly — he could speak like an adult and read books by the age of one year and seven months, and was adult-sized by the age of ten.
In Stephen King's The Green Mile, a supposedly elderly couple turned out to watch John Coffey's execution. They turn out to be the 30-something parents of the two dead girls that drove the story.
In The Stand, Nadine has prematurely grey hair which later turns completely white. She's in her mid-30s.
Although it's not emphasized as much in the books (and is dispelled somewhat by the later novels), the popular image of Severus Snape falls into this trope. Partly due to Adaptation Displacement by the much older Alan Rickman's brilliant performance as Snape in the movies, partly due to his being a peer to much older characters like Dumbledore and McGonagall, and partly due simply to Snape's own scowling personality, it's very easy to forget that he was barely in his thirties when the series began.
This is averted by Lupin in the books. Although he is described as ill-looking and prematurely greying (implied to be a side effect of his lycanthropy), he still looks his age:
Though quite young, his light brown hair was flecked with grey.
In Star Trek: New Frontier, Xy, the son of Burgoyne and Selar, is the chief science officer of the Excalibur...at 5 years old. He's cursed to rapidly age and die very young thanks to the intermingling of Hermat and Vulcan DNA until his mother gives her life to find him a life-extending drug.
In another Star TrekExpanded Universe novel, "Immortal Coil", Rhea McAdams becomes the new security officer of the Enterprise...despite being a barely two-week old android.
The story takes place in medieval France. 40 was considered pretty old, so to be bald at 36 is not unreasonable. (And even today, many men go bald in their mid-twenties.)
There's also the medieval Catholic custom of "taking the tonsure," which meant that members of the clergy shaved a circle on top of their head that coincidentally resembled male-pattern baldness. This is why Friar Tuck is always portrayed as bald, by the by.
Miles Vorkosigan tends to straddle this trope and it's inverse. His short height, slight build, and high pitched voice cause people to subconsciously register him as a child; however the facial lines caused by constant pain for most of his life means that only a slight adjustment of tone, expression, and body language is needed to convince people he is at least a decade older than he actually is.
In Lord of Light, a teenaged Yama caused an explosion which mortally wounded him, and necessitated his transfer into the only available body—that of a sixty year old man.
Eddard Stark looked older than 35 because of the streaks of white on his beard and the way he carried himself in general.
The youthful Asha Greyjoy sees an unfamiliar old man who calls her by name. It takes her a moment to realize that he's her younger brother Theon, who has been broken by torture.
Lupe dy Cazaril from The Curse of Chalion is only in his mid thirties, but not only is his beard mostly grey but by the time he mostly recovers from the debilitating aftereffects of his time as a Galley Slave he comes down with miracle-inducedterminal cancer.
Jackson Browne's song "Cocaine" has a line that goes "Son, it says here you're 27, but that's impossible. You look like you could be 45," due to the protagonist's cocaine use.
2 Broke Girls: In "And the Hold-Up", a second-season episode, three different characters give a Big "WHAT?!" when they find out that Han, who they had thought to be in his 50s, is only 29.
10 Things I Hate About You: In the TV adaptation, the character of Patrick Verona looked like he was around 19-21 years old, but was actually a high school junior. The actor who played him was only slightly older than he looked, being 22-23 when the series was shot. Walter even points this out to Kat, calling him her 'friend with the disturbingly deep voice who looks much older than 17.'
The 4400: Isabelle Tyler, the toddler daughter of two adult characters, ages herself to an adult, killing her mother in the process. As a three-year-old in the body of a twenty-something, she seduces a male character, has a sexual relationship with him and then blackmails him into staying when he threatens to leave her, because she's psychotic and murderous in addition to being really three years old. Squicky much?
Angel: Chronologically, Connor's only three, but due to the different flow of time between Earth and Quor'toth, he's in his late teens.
Battlestar Galactica (Reimagined): The Brother Cavil/Number One model of Cylon looks like an old man but is 30-40. No doubt being permanently old is one of the reasons he's so cranky, along with removing his own need for sleep.
The Brady Bunch: Jan and Peter Brady went from looking their ages (14 and 15) in the fourth season to looking 18, just a year later.
Buffy the Vampire Slayer: Dawn, who is created fully formed at age 14. On the other hand, she is also the Key, which is nearly as old as the universe.
CHiPs: A B-story in one episode contains Ponch becoming fixated over a model on a billboard. By the end of the episode his fellow officers finally give him a chance to meet the young woman, who turns out to be very young - 14 to be exact.
Diff'rent Strokes: The 1981 episode "The Older Man" – a crossover episode with The Facts of Life due to appearances by Lisa Whelchel and Mindy Cohn (as Blair and Natalie, respectively) – sees 15-year-old Kimberly pout over having to be a young teen-ager and unable to land a desirable date. Blair agrees to give Kimberly a wig and puts on makeup that makes her look like she's in her early 20s. This has unintended consequences when she lands a date with a 25-year-old man named Mike. Arnold and Willis know what this means and try to disrupt the date at the movie theater. Fortunately, Mr. Drummond finds out and intervenes before Mike even thinks about his next move – and Mike seems genuinely surprised (and aghast) when he learns he was dating someone who was in her mid-teens. (Fortunately for Mike, Drummond lets him off the hook because of Kimberly's deception, particularly because he could have had him arrested for any number of sex-related charges and caused him a lifetime of negative consequences.)
One episode ("The Doctor's Daughter") has a planet where everyone is born as an adult and with all the knowledge they need downloaded into them. The titular daughter, Jenny, is an example.
The Sontarans, a mass-produced clone race engaged in an unending war, are similar:
"I've had a good life. I'm nearly 12."
Earth: Final Conflict: Liam Kincaid, one of the revolving door protagonists, is born at the beginning of Season 2 and almost immediately grows to adulthood, both physically and mentally. With the memories of all 3 parents, including the show's Magnificent Bastard.
Friends: In one episode, Monica, who is in her mid to late twenties, dates and has sex with a young man who told her that he was a senior in college, while she tells him she's 22 (rather than 26). When she comes clean about her age, she is shocked to find out he lied as well, and is really a senior in high school. It was his first time, too, but she is not too happy doing what would "make one of us a felon in 48 states."
Similar, but slightly Squickier, in , Casey brings a date to show up Rebecca (who's with Cappie at the time) at a double date sorority party. Cut to her in bed with him...and his mother waking him up to go to school. To high school. He's 16.
Also, Heath's sister...does not look 15, much to Beaver's dismay when he hit on her during Parents' Week. Although you do have to Take Our Word for It....
Hannah Montana: In one early episode, a boy had a crush on Miley. The boy looked like he was around 13 or 14, which at the time was the same age as Miley. Eventually, he invites her to his birthday party, which to her shock had balloons and other party accessories like confetti. The boy was 11.
The Inbetweeners: One episode had a mechanic who was really fifteen but looked to be in his mid-thirties.
It's Always Sunny in Philadelphia: In one episode, Charlie starts a relationship with an Asian girl while his friends conspire to get her to participate in a wet T-shirt contest. To their horror, they discover that she's only 12 years old. Luckily, Frank is able to jump in front of the water blast aimed for her, and Charlie never so much as kissed her.
Law & Order: One episode had two fashion models, one the Victim of the Week and her "workmate" who both had a few racy photoshoots. The victim was 14 and her acquaintance is in the eighth grade.
Little House on the Prairie: The 1981 episode "Sylvia" was about Albert's friend (and very quickly, girlfriend), a 14-year-old girl who matures early and as a result, faces ridicule from the school. She will quickly become the target of a child rapist (a man wearing a metal clown mask) and — after the rapist impregnates her — the subject of both scandal (thanks to Mrs. Olesen spreading an outright lie that Albert had done the deed) and being callously cast out by her cold, uncaring father. In the end, Sylvia has another run-in with the rapist, and is killed after falling from a rickety ladder trying to escape.
Malcolm in the Middle: Malcolm and his Dad got in trouble because of this trope. Malcolm beat up a kid who was bullying him but was really 7 years old, despite being bigger than Malcolm. The kid's brother picked a fight with Hal (said brother is at least one head taller than Hal). We cut to Hal mentioning that there was no way to know he was 15.
Despite playing Mama in Mamas Family, Vicki Lawrence was only in her thirties at that time.
Mork and Mindy: Orkans are born looking old and grow younger looking as they age, so when they're old they look like babies. Jonathan Winters plays M&M's son in later seasons.
New Girl: The episode "Kids" contains Jess taking care of her boyfriend's 14-year-old daughter, who is also one of her pupils, and begins to fall hard for Nick. Meanwhile Nick himself brings home a woman he meets in an art museum, and we later find, she isn't that much older than the little girl Jess is taking care of.
Once Upon a Time: 28-year-old Emma Swan is stated to be 18 when she got pregnant with Henry. However, the flashback episode "Tallahassee" showed that her teenage self looked no different that herself in the present day, save for a pair of glasses and different hairstyle and clothes. She also looks no different than her present-day self in her jail flashbacks.
Power Rangers Operation Overdrive: Mackenzie Hartford looks like a 17-year-old when he first appears. Later in the series, he is revealed to be a 2-year-old android, which makes him the youngest ranger, even younger than Justin Stewart from Turbo.
The Sarah Connor Chronicles: Cameron can easily pass herself off as a teenager or twenty-something, but she is nowhere near as old, having been modeled to assassinate John Connor in the future by assuming the form of a woman he knows.
The Sarah Jane Adventures: Luke Smith, who is grown in an alien laboratory, is born in the first episode ("Invasion of the Bane") as 13/14-ish year old boy who is as capable as your average teen... in fact more. But he acts naive and innocent as he has no life experience.
Scrubs: Parodied in one episode, when the Janitor takes offence at Carla thinking he's forty-five, explaining he looks older because "I drink and smoke heavily, and work with chemicals, and sleep on my face". He's forty-three.
Sister Sister: One episode featured Tamera falling for a cute boy on her bus, who invited her to his birthday party. To her horror, it was his 12th birthday.
Space: Above and Beyond: The In Vitroes are decanted from their tanks with the apparent physical age of 18. Cooper Hawkes is just six years old at the beginning of the series, with T.C. McQueen being considerably older, but still younger than his middle-aged appearance would indicate.
Stargate SG-1: Another case of magical (or close enough) rapid aging is Adria, born from a regular character and aged into her apparent 20s in a matter of days.
Kes looks like a 20-something... but she's not human; she's actually about 2 years old when she joins up. Her species has an average lifespan of about 9 years, with the idea of making it to twelve being shocking.
Also, 20-25ish year old Seven of Nine has the emotional age of six when she joins the series, thanks to living as a Borg drone since that age. Her initial mannerisms and speech don't suggest it, but especially once you get to "The Raven", it's clear just how badly assimilation hurt her and how she hasn't been able to move on.
The Jem'Hadar of Star Trek: Deep Space Nine are able to fight within hours of being born from their test tubes. While no maximum age is given—they may even live as long as humans—they're considered "honored elders" by the age of twenty because they were created with almost no survival instinct to be soldiers and/or cannon fodder for the Dominion.
Many Vorta, being clones, are also younger than they look. Consider Weyoun, who has a propention for getting killed (often). Many of the Weyoun clones are merely months or even weeks old when we meet them, and *some* have lifespans shorter than a year.
The Twilight Zone: In the episode, "A Thing About Machines," the main character, Bartlett Finchley is said to be 48 years old, but the actor playing him is 55 (and looks much older) when the episode is filmed.
V (1983-85): Elizabeth, the half-human half-alien "starchild" from this Sci-Fi series. Like scores of other "magical" children in TV-land, she grew rapidly after conception (the typical TV Express Delivery) and after birth, becoming first a pre-teen girl and then undergoing a metamorphosis blatantly scripted so that they could swap the girl actress for a 20-year old actress in a white dress. She, being a starchild, had mystical healing powers! Even though neither of her parent races had such powers. Gah.
The X-Files: Gillian Anderson was 25 when she started playing Agent Dana Scully, who looks(though this is mainly due to the way she dresses) and acts several years older.
Older Than Feudalism: The Greco-Roman goddess Athena/Minerva was born fully grown (most images depict her as being about in her mid-twenties at the time of her birth). It's very telling that this is one of the less incredible aspects of her birth story. She's doesn't age, so it quickly turned into a case of Older than They Look.
When Artemis was born, her mother Leto gave her some nectar and ambrosia (the food of the gods), which caused her to grow up within a day. As such she was able to serve as midwife for the birth of her twin brother, Apollo.
The Táin Bó Cúailnge of Irish Mythology suggests that Cu Chulainn matured quite a bit earlier than most people do - he apparently wooed Emer and took up training with Scáthach at age six.
Adventures in Odyssey had an episode where two boys get stuck inside a computer and meet a boy named Gregory who despite looking like an old man of 70 was in fact 12 due to having his life sucked away by playing computer games. The adventure (along with Gregory) was just a virtual reality simulation.
Dizzy from the Guilty Gear games has the appearance and much of the maturity of a fully grown woman, but is actually only three years old, and has the innocence to match.
Also, Ky's son Sin... who is probably at maximum, five years old. At minimum, two.
Teira, one of the female companion choices in the Shadowlords series (fan-made expansion for Neverwinter Nights) is nineteen. Due to the side effects of a dangerous spell she was forced to use to escape a prison before the game begins, she looks like she is twenty-five or thirty.
The Numan◊ Rika in Phantasy Star IV looks to be in her late teens/early twenties, but is really only a year old.
Nei and Neifirst from Phantasy Star II also fit into this category only having existed for one and two years respectively.
Amoretta the Homunculus of Grim Grimoire measures her lifespan in days (about 3 months), despite having the body of a young woman.
Jack in BioShock is implied to be only a couple years old, yet he seems to be an adult.
You find an audio diary describing the progress of an accelerated growth treatment, but you may not immediately realize who the unnamed test subject is.
In BioShock Infinite, Zachary Comstock is the same age as Booker DeWitt, being an alternate reality version of him, but appears to be older due to the Luteces' experiments taking a toll on his health.
Cid Highwind in "Final Fantasy VII"". Despite being listed as only 32 years old, Cid looks like he's at least 42, and behaves older still. This may have something to do with Cid's apparent excessive drinking and smoking, plus his cynical, defeatist attitude since the suspension of the Shinra Space Programme. He is also a classic Oyaji character, which a character may be regardless of age. ("Oyaji" are generally men who act like they're middle-aged, complete with perceived "middle-aged man habits" such as smoking and drinking. Whilst many are older guys, the actual age of the character is not important as being oyaji in the character-sense is about attitude and behaviour, not actual age.
It's even pointed out that Luke is essentially only seven years old.
Replicants? Just by looking, it's hard to put Tear and Asch as being only 16 and 17, respectively.
Van comes off as a middle-aged man, at least in the English version, but according to his bio he's only 27. It doesn't help that his hair color makes it look as though his hair is graying.
It's suggested that he invoked this trope in the skit "Brother And Sister", as Tear tells Luke that he grew a beard to seem older in response to other members of the Order being jealous of his rising so high so quickly.
Otacon affectionately calls him "Old Snake" in Gratuitous English in the Japanese version, although it was removed from the English one.
His younger brother, Solidus, looked a lot older than him in MGS2.
Phoenix Wright: Ace Attorney - Dual Destinies : Since Phoenix was 24 and Apollo 23 many people believed Athena Cykes would be in her early twenties, but she is actually 18. No player would suggest she is only 18 because it should be impossible for her to finish high school with such age and work as a lawyer so fast.
Simon Blackquill, with handcuffs on the wrist, a height of 6' 2'', shadows under his eyes and black/white hair looks older than Phoenix, but he is just 28. This becomes rather unsettling when you realize his 37 year old sister looks much younger than him.
The main character Vayne of Mana Khemia Alchemists Of Alrevis, being an artificially-made Mana, looks like any normal 16-17 year old teenager, except that he was actually around six years old.
Angela Orosco from Silent Hill 2 is only 19, but looks at least in her 30s. This was done intentionally by the animators, to show how her past of sexual abuse and killing her abusive father has prematurely aged her and taken a physical, as well as emotional, toll on her. It was also done to separate her from young and supposedly innocent characters, like Laura, and to emphasize that she isn't to be sexualized in any way, as much of the symbolism in the game places emphasis on sexuality. Originally, the character was conceptualized as 15 or 16, but the voice actress chosen to portray her gave her an older-sounding voice, and the design team changed her accordingly.
Lisa Garland from Silent Hill Origins acts as a twenty-something woman, specially when you consider that she slept with Dr. Kauffmann, but since she was 23 in Silent Hill, she is suposed to be around 16 in this game.
Considering that the Lisa in ''Silent Hill could have been a manifestation and not real, in Origins she could be anywhere from 16-23.
Chuck Downfield of Backyard Football looks like he's in his 20s. His age? 9. He just knows the game so well and dresses like an adult.
The vat-grown people from Shin Megami Tensei II (that is, Aleph, Beth, Daleth, Gimmel and Zayin) were grown to adulthood in a single day. This means that the main character is only a few days old from the start.
Ramon Salazar of Resident Evil 4 has the skin of a man in his seventies (and the stature of a twelve year old boy), but claims to be twenty years old.
And for much of his life (until he went into torpor for 600 years and became the Fou Empire's King in the Mountain) Fou-lu himself would be an example of this trope—only finally "catching up" after unifying the future Fou Empire in a single generation. It's implied in the game (and overtly depicted in the Comic Book Adaptation) that Fou-lu, much like his Literal Split Personality Ryu, ended up being summoned into the world looking like a young adult.
Mass Effect 2 has Grunt, who is within a week old when you "recruit" him. Despite him looking like he's weathered at least a few years of life, or maybe a couple of month's worth of battling. (Still, compared to other Krogan, he's pretty "smooth-as-a-baby's-behind" material.)
In Warcraft, some orcs, including Rend and Maim Blackhand are artificially aged, and thus become adults years before they would naturally grow to that point.
Wrathion, the uncorrupted black dragon, has the human appearance of a youngish looking man with a goatee. His true form is that of a black dragon ''whelp', a dragonling a couple feet long, making for a rare example of a dragon that stays human because he's more imposing that way. He's actually only two years old.
Jak and Daxter's Jak, from the second game on. According to his bio on the official Jak X site, the 18-year-old "is a seasoned hero, with etched lines on his face that show the many challenges he's overcome, and the many adventures he's had to endure." The facial hair doesn't help.
Keira gets hit by this too. She's one year younger than Jak but was even on the Fanservice Cover of a magazine despite being around fourteen at the time. She looks young but vaguely between fifteen and nineteen.
Kreia from Knights of the Old Republic II looks to be in her 70s. However, according to her creator, Chris Avellone, she's only around 50. The reason for her older appearance is likely due to her heavy use of Dark Side powers since the Mandalorian Wars.
Jim Raynor in Starcraft II is 34 despite looking 20-years older than that.
Tweek from Fur Fighters is less then a day old, making him the youngest of the Fur Fighters
In Super Dangan Ronpa 2, there's SHSL/Ultimate Coach Nekomaru Nidai who looks well over his 20s, maybe even older, when compared to his classmates who are around 16-17 years old. There's nothing said that confirms or even implies that he was held back in school like Yasuhiro Hagakure, or anything of the sort, which means he may as well be the same age as the rest of them.
In the SSI Gold Box game Curse of the Azure Bonds, the character screen of the optional NPC Alias lists her age as "2" despite her being an experienced adult fighter. As this is not explained in-game, some players might assume it to have been a developer oversight but anyone familiar with her Forgotten Realms backstory knows that she was actually created artificially and that the listed age is accurate.
Swaine in Ni No Kuni. Due to his life as a wandering thief, he has an extremely run-down appearance with scraggly hair, an untrimmed beard, a bony face, and baggy eyes. He's no older than thirty. When the party travels fifteen years into the past and meets his younger self, he appears to be about the same age as Oliver, if not a little younger.
Jan Jansen in Baldur's Gate 2 has Perma Stubble that's partially gray and a very calloused face, and sounds like (if he was human) he'd probably be well into his sixties. Every in-game indication of his age indicates he's barely adult by gnomish standards (which would still make him over thirty years old, but still).
Fate/stay night - Token Mini-Moe Ilya's maids and apparent caretakers appear to be around twenty and are a bit... strange, and have about five minutes total screentime. They're actually two year olds. They're also fairly lethal combat homunculi, whom Ilya made.
Tsukihime: While the 800 year old Arcueid only looks like she's in her late teens to early twenties she may well be much younger than that, mentally, as she was put into sleep mode when she wasn't killing Fallen True Ancestors, and after the True Ancestors died out, whenever Roa's incarnations were inactive.
Phi: You must have done a lot of drugs to look like that at 22.
Actually a subversion—Sigma believes he's 22, and because he's the viewpoint character the player sees him as he sees himself, which is to say, as he looked at age 22, but in fact the mind of his 22-year-old self has been implanted in his own body at age 65.
MAG ISA: Kyle looks old for a 23 year old. Must be all those damn steroids...
Page 78TwoKinds shows this trope with a whole race. Flora, one of the main characters, who looks and acts as if she is in her early twenties, is only 11 years old. However, her kind only DO live into their early twenties. Late twenties at best.
Dr. Schtein from String Theory is apparently only 34 despite the lines on his face and his completely white hair.
In Nectar of the Gods, Bacchus' father, Apollo, is MUCH younger than he looks, he has the goatee, the benjamin franklin hairdo, the old man glasses, the wrinkles and near white hair to make it almost obvious he's in his mid 70s.... he's actually 46.
Kit from Feywinds has this. she's a fox turned girl and fox age doesn't equal human age so she looks early 20's but is actually not anywhere near that. she acts accordingly though with a childish but quirky personality and can be very naive. She looks like an adult, age wise is a child but has the mentality of a girl in her mid to late teens, albeit a clueless one. Though the author of the comic has said she likes us to not think about how old the character actually is.
Cole Richards from PvP looks like he's in his mid-40s, but he states in an early strip that he's about to turn 30. Moreover, he was college roommates with Brent, Robbie and Jase, who look about right for being in their late 20s.
The Cyantian Chronicles: All of Exotica Genoworks' creations suffer from this since they are designed to mature to something like 12 to 15 in only 4 or 5 years.
Spinnerette, there was a lot of surprise when "Evil Spinnerette" turned out to be just 16 years old, she looks like she should be in her late twenties at least. This acts as a point of contrast with "good" Spinny, a grad student who gets mistaken for a teenager.
One of the school psychiatrists at the Whateley Academy is in his mid-thirties (or so, based on author descriptions) but looks like Dr. Bellows from "I Dream of Jeannie", so he appears to be 55 or 60. One protagonist has even researched the psychiatrist, and has lampshaded this.
Fifteen-year-old Chou Lee (Bladedancer) apparently looks like Zhang Ziyi.
Belpheobe is a clone of Jobe's ideal girlfriend with the memories of Belphegor. Pheobe is then legally entered as Jobe and Belphegors' daughter, with Jobe the mother (as he is turning into his ideal drow girlfriend. Pheobe is therefore "0 going on 16"
Robert "Bobby"Jacks, Adam Dodd, and Nicole Husher from Survival of the Fittest are all teenagers, yet they look like young adults. Bobby is a large, muscular, professional boxer who has spent almost his entire life devoted to the sport, causing him to look much older; Dodd had always looked a bit older than he actually was, but the horrors of the first game added a great deal to that; Nicole, meanwhile, developed very quickly due to an early onset of puberty, causing her to appear to be a few years older than she actually is, with predictable results when she reached middle school-age.
In Super Stories, Veldron's robot duplicates are always built to look older and less attractive than him. This is because, when given the opportunity to make a false image, most people would assume the opposite.
In Darwin's Soldiers, most Pelvanida experiments are much younger than they look. This is justified because they were grown with accelerated growth chambers.
Neku looks and acts like a 17 year old but is 6.
Snow looks and acts like a twenty year old but is the same age as Neku.
Chase looks and acts like a twelve year old. He is two years old.
John "Johnny" Smith is an extreme case. He looks and acts like a thirty four year old. He is seven.
Sabre 9 looks and acts like a thirty one year old. He is eight.
Ice looks and acts like like a thirty two year old. He is the same age as Sabre 9.
Walter "Wally" O'Pierce looks and acts like a thirty four year old. He is ten.
Eve of Dragomirs Diary was born a baby, but within months grew to the size of a teenager. This may have something to do with the story being set in a video game - or it could be something far more sinister.
Chakona Space: Shadowcrest is only 12 or 13 when she is critically wounded. After being "processed", she is once again intact but she looks like she's 20.
Leanna and most other artificially-grown slaves wind up suffering this trope for a while.
In My Little Pony: Friendship Is Magic, Mayor Mare, the supposedly elderly grey-maned mayor of Ponyville, is revealed to have naturally pink hair that she dyes grey. It's implied she does that to give herself an air of professionalism, and that her age is far more ambiguous than one might think.
Lloyd in the later episodes of Ninjago looks to be in his late teens or early twenties. He's actually about seven to ten, thanks to a magical powder called Tomorrow's Tea.
Ms. Censordoll from Moral Orel looks like she could easily be in her seventies or eighties, but when someone calls her a senior citizen she shows her ID and it turns out she just turned forty. It's heavily implied and confirmed by Word of God that this and her obsession with eggs comes from her mother having her ovaries removed at a young age.
Hans Moleman on The Simpsons: even though he looks like an old man, he confessed during the Alcoholics Anonymous meeting on the Season 4 episode "Duffless" that he's really 31 years old (and looks like an old man due to his alcoholism). This has become a one-off joke, because in later episodes, Hans Moleman is usually seen at the Springfield Retirement Home.
In one of the new episodes though there's an even older Moleman who he's the son of. They even participate in a father-son wheelebarrow race at the home. It may be possible he's just visiting him all the time. Maybe?
Also Homer Simpson is younger than he looks, according to the Season 4 episode "Lisa the Beauty Queen". While at a carnival, Homer tries his luck at the "Guess Your Age and Weight" booth. The mind reader guesses that Homer is 53 years old and 420 pounds. Homer then laughs at him and reveals that he's 36 years old (though later episodes have him as 38 or 39, depending) and 239 pounds, which disturbs the mind reader.
Before Flanderization, Mr. Burns was only 81, but looked older because he went bald during his college years, according to the Season 2 episode "Simpson and Delilah". The later episodes have Mr. Burns as somewhere in the 100s ("Homer the Smithers" confirmed that he was 104; "Goo Goo Gai Pan" had him as 109, with a driver's license that expired in 1909). That said, in "The Regina Monologues" and "Them, Robot" imply that Mr. Burns' age has four digits in it (in the former episode, his PIN number for his bank card is his age [PIN numbers are four digits long, for those who live in countries that don't have bank cards or AT Ms or have them in a different format than in America], and in "Them, Robot," Homer asks Mr. Burns how old he really is, and Mr. Burns says, "Well, it has four digits...").
Thailog, of Gargoyles fame, being a clone who's been artificially aged, reached the end of Gargoyle adolescence after a mere nineteen weeks. Especially impressive, when you consider that Gargoyles live longer and age slower than humans as it is.
In an episode of The Ren & Stimpy Show, "Fake Dad", a six-foot-tall, overweight convicted criminal with hairy arms and 5 O'Clock shadow, who calls himself Kowalski, is 10 years old.
Maybe they measure age in dog years.
Joseph Gribble in King of the Hill. He hit extreme growth-spurt puberty before turning 13, before Bobby gets a chance and he's older (despite being late-bloomer). He was given an adult menu at a restaurant and assumed of wanting a beer like the parents.
Cotton Hill in his younger years after he married Tillie and around Hank's birth and childhood, even though he's around his mid 20's-early to mid 30's he still looks like an old man around 60 just with brown hair.
In Galaxy Rangers, Shane Gooseman looks about 25, but the second-to-last episode reveals he is nineteen, meaning he was 17-18 as of the pilot episode. As he is also stated to be the "youngest" of the Super Soldier project that created him, the other Supretroopers can't be any older than thirty.
Superboy in Young Justice, having the appearance and mentality of a sixteen year old, but is actually sixteen weeks old having been born in a test tube.
Lampshaded after the Time Skip in the second season. When Wendy asks Conner how old he is, he truthfully responds by telling her he's six. After seeing her shocked reaction, he quickly corrects himself and tries to claim that he's actually twenty-two.
Also Captain Marvel who is actually a ten year old kid (fifteen in season two) with his powers helping him to appear like an adult.
Smurfette in The Smurfs, despite being an adult Smurf, is really only about a few years old, being a magically-created Smurf.
DJ, Alejandro, Sierra, Leshawna and Trent from Total Drama Island look like adults in their late twenties-mid thirties, despite their real age being 16-18.
In Revenge of the Island, Brick and Jo look older than their actual age of 16.
The principal in Alvin and the Chipmunks Meet The Wolfman. Dave mistakes her for being over-fifty, when she's really only thirty. She still has her blonde hair though. Her (apparent) early aging is due to how stressful her job is; she's getting an early retirement.
In the original 1985 ThunderCats, Lion-O appears 20, despite really only being about 10-11 originally. Thanks to a faulty cryosleep chamber, his aging wasn't as delayed as the other two young ThunderCats, WilyKit and WilyKat.
In Pepper Ann, P.A. befriends Effie Shrug, a new student who is exceedingly intelligent and taller than she is. The two get along well, although the viewers learn that Effie can be quite threatening to get what she wants. She's something of a Social Darwinist. Pepper Ann invites her over to her house, Moose sees Effie and is immediately horrified. Effie reveals that she was previously an elementary school student. She'll be nine next month.
Cassie from Bounty Hamster looks and sounds like she's in her late teens, but she's actually 13.
Robot Girl Jenny of My Life as a Teenage Robot once had to spend an episode being demoted from high school to kindergarden because she's technically "only five years old," having been built five years ago, despite being designed as a teenager.
Pinky and the Brain may look like adult mice, but their actual ages suggest otherwise. Take, for instance, this exchange from the Christmas episode:
The Brain: Now our only problem is that we need one billion Noodle Noggin dolls. To make all of them ourselves would take 137 years. Pinky: Oh, well, we'd be pretty old by then, wouldn't we? The Brain: Yes, I believe we'd be 139.
Real-life mice generally are adults by 2 years old, though.
Octus from Sym-Bionic Titan. Although he's able to take both the guise of a teenager and a middle-aged man, he was heavily implied to have been completed shortly before he, Lance and Ilana fled Galaluna.
Heloise from Jimmy Two-Shoes is fourteen at the start of the series, fifteen in season 2, but looks like an elementary student. Justified in the original concept for the show, where she's in Hell and can't age.
The Powerpuff Girls. They were born/created the age they are throughout the whole series and start kindergarten shortly after their "birth." As they're the same age throughout the whole show, they're probably less than one year old. The Rowdyruff Boys were also created (twice!) at the age they are, which makes them even younger although appearing to be kindergarten-aged boys as well.
Place information about specific people in the category below this one.
In general, children who go into puberty at an early age can look older than they are, especially if those signs of puberty are visible, such as height and voice deepening (in both sexes), muscle development (in male children) and breast growth (in female children)
Hard living in general can make you look older. Homeless people often look middle-aged in their late twenties, due to poor health practices and chronic stress. Back when it was common practice for women to have 10 or more kids while living on a fairly poor diet, they aged pretty fast too. And people who do very hard labour that's risky to your health, such as coal mining, often end up Younger than They Look as well.
Anyone born with progeria, a disease that causes rapid aging; sadly, sufferers never become As Old As They Look, rarely living past their teens. The disease was the basis for Jack, as seen above.
Some drugs in Real Life can do this, too. Heroin addicts in their early 20's can easily appear 35-40 years old.
True for most drugs. Substance abuse is notorious for rapidly accelerating the accumulation of cellular damage and decay we normally identify as "aging".
This is the basis of the "Faces of Meth" campaign, which uses before and after photos to highlight just how much damage the drug can do. For an example, former America's Next Top Model contestant Jael Strauss is 28 in that second photo (and those two were only taken six years apart.)
This is generally true for most people in extremely stressful jobs. Most American Presidents seem to age around a decade for each term—so if you get that second term, you can look forward to having aged twenty years in just eight. Just look at pictures of George W. Bush before and after his term. Look at pictures of Barack Obama before his term and during his term.
Similarly, having children tends to age most men and (especially) women considerably. Many young-looking women who have children look quite a bit older when their child reaches his/her first birthday.
Anorexia can cause this-the starvation causes muscle to waste away and skin to become looser, creating wrinkles. The lack of nutrients also thin the hair, making it look older. Marya Hornbacher talks about this in her memoir Wasted-in her late teens/early twenties, a barman guessed her age at thirty-six because the wrinkles made her look much older than she really was.
Heavy smoking can also cause skin and hair to age by both drying them out and by restricting the amount of oxygen they get by constricting blood vessels with nicotine and by blocking oxygen transport with carbon monoxide. This makes hair brittle and likely to gray sooner, and it makes skin lose its elasticity, causing it to wrinkle early. (Plus its effects on how "young" you are on the inside!)
It also makes your voice sound raspier and, thus, "older." Many 20-something year old women who are heavy smokers sound more like they're in their middle ages.
The stress from playing a role in Military Command (i.e. sending hundreds of soldiers to their deaths) will age you majorly.
It ages those involved psychologically - so their facial expression changes in regards to this, they adopt nasty little habits which are a trademark of old men, and so on. But military men are bodily very fit, in many cases stronger and quicker than men of the same age or younger.
Most college (and in some cases, high school) athletes tend to look at least 2-3 years older than they are. This is mainly because they are rather built, especially if they are a football player, and are often taller than the average male height (the average male height is 5'10'). For example, an 18-year-old freshman basketball player may look like he's around 20-21 years old.
LeBron James is probably the best example, having looked to be in his 30s since his late teens when he started in the NBA. how many people look like this◊ at 19?
In New Zealand, anyone who looks under 25 is asked for photo identification when purchasing alcohol or tobacco (restricted to ages 18 and over) to avert this trope and prevent retailers from getting themselves into trouble with the law.
Same thing happens in the UK.
Also quite common in the US.
Men (and boys) can look considerably older depending on their hair. A naturally balding man tends to look older than they might actually be. Facial hair and facial hair style also can make a man or teenage boy look more aged. Combining the two can leave observers very unclear as to how old the man really is.
Some believe that married men typically look older than they are. It may be due to their tendency to dress and act more conservatively than swinging singles. Others believe that it may be due to the settling down (and flabbiness) that comes with domestic life. Now being family men, they should no longer have an incentive to obsess over their looks that much, since they shouldn't be thinking about attracting other women anyway. Also, having a wife and family is a full time job and they no longer have the downtime they had as singles. However, others believe that after a certain age, single men tend to look older than they are due to the fact that they don't have as much of a social network as married men do. Some hypothesize that unlike married men, who have a wife and family to keep them in check, older single men tend to hold on to habits of their youth longer than they should, such as partying, eating what they want, womanizing, refusing to slow down, and various forms of freewheeling that may be considered less healthy at their age.
Real Housewife Kim Zolciak looks like a 40 year old who's aged well. She's was actually born in 1978 making her 34 (at the time of this writing) This is made even worse that her oldest child was born in 1997 making her 16.
Fellow troper and musician Dartxker Bitsby (real name Jovontae Pride) is only 14, yet could pass for 19.
Mila Kunis got her first major role playing Jackie on That '70s Show when she was just 14, even though everyone auditioning was required to be 18 or older. When Mila was asked if she was 18, she said that she would be, but didn't specify when. Eventually she was found out, but was still considered the best fit for the part.
There's a 1979 WPIX (CW affiliate in New York City) clip on YouTube of their newscast where one of the anchors is a man named Bill Jorgensen. Watch the clip and try to guess how old he is. He's 52 in the clip, which would make him around 81-82 right now (Jorgensen's still alive as far as I know)
Hollywood lore has it that three-time Oscar winner Walter Brennan's career took off after he lost his teeth in a fight and found that without them he could play old men from around the 1930s onwards - when he was only in his '30s!
Florence Owens Thompson, the woman in this famous photograph◊ by Dorothea Lange was thirty-two when it was taken. It showed the devastating effects of The Great Depression more than words possibly could.
The famous picture of the Afghan girl◊ from National Geographic has many people wondering if she's really a "girl". She was 12 years old when the picture was taken, but because of the stress of being a refugee, she looks to be in her mid-20s. And when the photographer (Steve McCurry) met her again, this is how she looked at 35 years of age.
In 1970, the much-older-looking Mary Ann Vecchio was, in fact, a 14-year-old runaway. Jon Filo's photograph of her crying over Jeffry Miller, who'd been killed in the Kent State shootings, won him a Pulitzer Prize in 1971.
David Gregory of MSNBC appears as of writing (2012) to be in his early 50s, mostly because of his silvery hair and slightly aged face. He was born in 1970.
Nobody could tell how old Michael Jackson was in his later years, mainly because of his vitiligo that made his skin white (he looks much whiter in the photos because of the camera lightning). When he was young, however (Thriller and before), he looked a bit old for his age, particularly when he was a kid, looking to be around 11 or 12 when he was just 8 or 9. Oh, and look at this photo.◊ Take a good look at it. He was not yet twenty.
Michael Gross (Steven Keaton from Family Ties) shares the same birthdate with Meredith Baxter (Elyse), but while Baxter looked her age when she was cast for the series, Gross looked about 5-10 years older largely thanks to his thinning, prematurely gray hair.
At the age of 15, Traci Lords claimed to be 20, used a fake ID, and started appearing in porn magazines and films. Authorities only caught on three years later. Some rumors claim that she tipped off the authorities herself to force the issue so she could get out of the business without having her work follow her. Since she only did one film after she was 18, everything else is illegal in the US.
Hitler was said to have aged rapidly in appearance during the final years of World War II, after having held uncannily the same appearance from the mid-1920s to 1943.
Metal singer Ivan Moody, vocalist for Five Finger Death Punch. Take a good long look at this photo.◊ And this one.◊ He's only 31. He looks at least 15 years older than that. This is especially strange because he was 27 when his band's first album released, and looked that age.
Ritchie Valens practically defines this trope. He died when he was just 17 years old. Seriously, look at this dude.◊ Who the heck looks like that at 17?!! Twice that age, maybe.
R. Lee Ermey looked to be a mid-50s gunnery sergeant in Full Metal Jacket. He was only 42 when the film was shot. His look has changed incredibly little since then.
Tommy Lee Jones. He falls squarely into the trope due to his signature craggy facial skin which appears to make him look older than he is. To put this in perspective, the ages of the four leads in Space Cowboys: Clint Eastwood (70 during the film's shooting), James Garner (72), Donald Sutherland (65), and Tommy Lee Jones (54). Jones is 11 years younger than Sutherland and nearly 20 to the others, yet he is portrayed as being around the same age as his co-stars in a film where a running gag is that many of their peers from their training days decades ago are all dead from old age (and Jones was fifty-four!).
Both Sherman Hemsley and John Amos got away with playing the husbands to women twenty years older than them and the father to sons played by actors only ten years their junior in the Norman Lear produced sitcoms The Jeffersons and Good Times. Hemsley was 36 when he started playing the role and John Amos 35, yet both were playing someone roughly 50. It helped that in both cases they were prematurely bald.
Zara is a 13 year old girl from England, yet she looks she's pushing 60. That's because she has a rare condition know as Congenital Generalized Lipodistrophy, which causes the supporting fatty tissue under the skin to crumble while the skin continues to grow, making her appear older.
Ryan Clark, the lead singer for the heavy metal band Demon Hunter. The music video for his band's 'Infected' was shot in 2002, when he was just 23. But due to the large beard he had and his lack of hair (and he's a little fat), he looked to be around 10 years older or so. He's now at the age of 32 and looks that age, though.
Whitman Mayo was only 40 when he portrayed Grady Wilson on Sanford and Son.
Steve Martin's hair began to grey at an early age. Because of this, even in his twenties, he looked like he was much older.
George Clooney had a full head of grey hair before he hit the half-century age in 2011.
Leon Botha, who had the aforementioned genetic disease Progeria, lived to be 26, but looked like he was over 100 years old. Sadly, he was the oldest person on record to have had the disease.
Some of the people on Intervention who are hard into drugs may be in their early 20s, but look like they're an average 30 something.
Stephanie Cole has specialized in playing women much older than she is. She was the elderly Mrs. Featherstone in Open All Hours in her 40s, and the retiree Diana Trent from Waiting for God when she was in her 50s (opposite Graham Crowden, who was born 20 years earlier).
So has Edie McClurg, on the other side of the pond. Throughout the 1980s, when she was in her 30s, she convincingly played characters that were meant to be a good 10 years or more older than she was. For example, McClurg was only 34 when she played Grace, the Maiden Aunt school secretary, in Ferris Bueller's Day Off. For an interesting bit of juxtaposition in this film, also keep in mind that Cameron Frye's actor, Alan Ruck, was perfectly believable as a high-school senior despite being 29. That's right — Grace and Cameron are only five years apart in age.
John Thaw would have been between 33 and 37 when he played Jack Regan in The Sweeney, but looks well into his forties- partly reinforced by the way he acts as well. Thaw himself apparently said "I was born looking 50".
Saoirse Ronan is 18, but looks like she's in her twenties. This is especially strange since only three years ago, she played a fourteen year old in The Lovely Bones, and looked that age.
Dioxin poisoning causes serious acne problems, which causes rapid aging. Victor Yushchenko, then in his late 40s, underwent this during a bitter campaign for presidency of the Ukraine, as seen here◊
Seth Rogen, especially in his earlier films, looked like he could easily be in his mid-thirties, though he was born in 1982 and would have been in his twenties. Rogen is pretty well aware of his "old" looks. He occasionally jokes about it in interviews. This actually caused problems when casting Superbad, since originally Rogen was going to play one of the main characters, a high school senior. Because of looking way older than he was (25 at the time), the role went to Jonah Hill. Hill actually is only a year younger than Rogen, but is a case of Older than They Look.
Bill Hader in some of his films (namely Superbad and Forgetting Sarah Marshall) looks considerably older than he really is.
Jason Segel. All of Apatow's "stock actors" (except for Jonah Hill, who actually looks younger than he is) look older than they really are.
When jazz saxophonist Charlie Parker died at age 34 due to heavy substance abuse, the coroner mistakenly estimated his age at between 50-60 years old.
This photo◊ of George Orwell had been taken when he was 30 years old. He could have been anywhere from 45 to 60 by looks only. 7 years later◊ he still looked like a grandpa. 12 years later◊ and suffering from tuberculosis, he was still unchanged, so it could not be blamed on poor living conditions only.
He's always looked about 10 years older than his real age. Here he is at 24◊ (Oz is on the far left), and he was around 33 when this◊ was taken.
Many of the WWE wrestlers. For example, Wade Barrett is only 31. He looks more like he's in his early-40's. Stephanie McMahon, after her voice went through a radical change in 2002-2003 (most likely due to all the screaming she was doing before then), definitely sounded much older than she really was.
Shane Harper from Good Luck Charlie looks like he's around 20-22 years old. He's 18. Made even worse by the fact that he was 16 in the early episodes of the show, and still looked the same. How many people really look like this at 16?
To put it in layman's terms: In season 1 of the show, he was 16, playing a 17-year-old character who looked like he was 20.
George Michael seemed to have aged rapidly since he hit his 40s.
Don Rickles unfortunately looks like he's in his 80s, but he always looked unmistakably old for his age until at most 20 years ago. Which is kind of funny, since he still possesses the voice of a 20-something guy from Boston.
Jeremy Clarkson of Top Gear has consistently looked at least ten years older than his real age for some time now. It's a little hard to believe he's only nine years older than Richard Hammond.
Robin Williams looks his age, if not a little younger, but he seemed to have aged badly as a young man. He was in his late 20s when he was on Mork and Mindy, but looked like he was in his 40s. Williams was into drugs and heavy drinking during his early career, which could have contributed to this.
Max von Sydow has looked about 75 since the day he was born. When he did The Exorcist, he was 44, looked absolutely ancient. Now he is 82, and looks rather spritely.
To be fair, Dick Smith did a very good age makeup on von Sydow for The Exorcist; you just don't notice it because of the flashier work on Linda Blair. Look at the center-right image here and you'll have a better idea of what he actually looked like then.
He was in his TWENTIES when he played Antonius Block in The Seventh Seal. See it and you won't believe it.
Ernie Pyle, American journalist and World War II soldier was 44 when he died. When he died he looked like he was in his 60s or 70s.
Austin St. John (a.k.a. The Red Ranger) was only 18 years old when he first started playing Jason Lee Scott. He looked more like he was about 20-22. It didn't help that his character was supposed to be 15. He actually seemed age appropriate a good amount of the time, but his build made him seem older. Still, it's a little hard to believe he was the youngest of the original six, as Jason David Frank, who was 19 at the time, looked fairly age appropriate.
Jason Narvy (Skull) was only 19 when filming began. He looked to be around 23 or so, as did Paul Schrier (Bulk), who was 23 for real.
Wilford Brimley for years was a shining example of this trope. To wit: He was only 50 years old when he was cast in Cocoon, but was able to portray a convincing elderly man with just his hair whitened. And this◊ is how he looked when he was in The Waltons. He was in his early 40s at the time.
It's amazing how many people are shocked to discover that swimsuit model Kate Upton hit it big when she wasn't even 21 (though she is now - she was born in 1992).
Miley Cyrus was once mistaken for a 40-year-old woman by a bystander who offered her face cream, despite being 18 years old at the time.
Michael Douglas, in his mid-50s, looked about ten years older, because he seemed to be trying desperately to hide how old he was(the new, young wife might have had something to do with that), now, in his late-60s, he seems to have made peace with his age, and actually looks younger because of it.
Topol was only in his mid-thirties when he Played Tevye in the film version of Fiddler on the Roof. But he was able to convincingly play a 45 year old Russian farmer who'd had a rough life. See pic here.
NBA player Greg Oden is 24 but according to pictures, he looks to be in his 30s.
Fergie actually used to look younger than she really was (she was in her early 30s when her debut album was being promoted, but looked like she was around 24-25). But in recent years, she seemed to have aged rapidly, and she is now in her mid-30s but looks like she's in her 40s. (This can be chalked up to a drug addiction past and once she got sober, she started looking younger. Her aging now can be chalked up to plastic surgery and pregnancy.)
Fergie as an example goes back to her Kids Incorporated days; particularly the last two seasons she was a cast member. She looks roughly early high-school age when she was actually 13-14 those seasons.
Alice Cooper now looks really good for being in his 60s, but he used to look far older than he really was. This is him in his high school yearbook,◊ looking to be around his mid-20s. By the time he actually did hit his 20s, he looked to be somewhere in his 30s. He continued to look older than he really was until he hit his 40s, when he aged considerably well and slowly converted to being Older Than He Looks.
Christian Weston Chandler, creator of Sonichu, looks about fifty when he's only thirty.
Vladimir Illych Lenin got his trademark figure which he held for life when he was just 25◊ and his photos from the late 40s to early 50s actually show him less aged. This is why a Russian journalist and historian said: "It would be hard for modern people to imagine Lenin in his younger years".
Taylor Momsen, due to her Goth appearance looked like she was at least 20. At 19 she looks closer to that. Though pre-Goth she looked her age like on the first season of Gossip Girl.
Alisha Dean was a 13-year old girl who became famous for abusing statutory rape laws. She had a Facebook page where she claimed to be 19 and divorced, and completely looked the part. She had a habit of seducing older men through her Facebook page, arranging meetings with them to have sex, and then turning them in. She sent THREE men to jail in this manner, reportedly just for fun. Her father did nothing to stop her, instead agreeing that "these laws are there to prevent this from happening". Never mind that the girl even had a fake ID with her fake age, meaning that anyone who actually tried to verify her age could still be duped.
Randy Blythe from Lamb Of God is only in his early 40s but looks like he could be 5-10 years older.
Courtney Stodden looks like she's in her mid-twenties at the youngest. She participated in the Miss Teen Washington pageant in 2010...at age 16. Squick comes into play when you take into account that she married Doug Hutchison in 2011. They may look like an age-appropriate couple, but she was 16 when they married...and he was 51.
Malcolm Mcdowell for most of his career post 1980. In A Clockwork Orange, he was 28 when he did the role but he did look reasonably young at the time. By the late 1980s, his hair went white overnight and he lost his young Alex looks. And he started getting a considerable number of "elderly man" roles despite the fact that he only just turned 70 in 2012. Mr. Mcdowell has confessed that he has no one to fault but himself.
This◊ is a photo of Adventure Time creator Pendleton Ward. He was born in July 1982. He's only thirty.
Savannah Hudson, who appeared on season 8 of America's Got Talent, looks to be in her late teens despite being only thirteen years old. She looks to be a similar age in her group's music video, despite being eleven years old at the time.
J. Elvis Weinstein, one of the original cast members of Mystery Science Theater 3000 (he was Dr. Erhardt and Tom Servo's first puppeteer), was only seventeen when the show first started on KTMA, and he was only fifteen when he first got into comedy. According to certain interviews with him, many people didn't suspect that he was really so young and were surprised when he revealed his age to them. He does look more like his actual age now, however.
Larry David has looked like an old man since the 90s, due to having balding white hair and glasses when he was in his 40s. He was only 52 when he started doing Curb Your Enthusiasm, but looked about 70. His friend Richard Lewis is older than him by a few days, as is Bob Einstein (who plays Marty Funkhauser) (four years older than him), yet both look younger. His age is played for laughs in the show: he's retired because of wealth not age, he has a wife who looks much younger than him, he always dresses like he did in his 20s (wearing sneakers), and his father is still alive.
Lorde, depending on her make-up and how she's dressed, often looks about 30 (she was born in 1996). There was a picture going around that was of her and the 34-year-old Beyoncé where they looked the same age. Furthermore, a face swap made Beyoncé with Lorde's face made her look like she was really old.
Hulk Hogan started going bald at a pretty young age and was completely bald by his mid-30s so he's looked pretty old for a while. Granted, he looks his age now, though.
Ric Flair is 65 and looks about 10 years older. He aged rapidly in the 2000s to the point that he looks like a completely different person than he did in the 90s. Compare this image to this one.◊