[[quoteright:157:[[Vidoegame/SuperMarioBros http://static.tvtropes.org/pmwiki/pub/images/mario_sizeshifter_1587.jpg]]]]
[[caption-width-right:157:Mario gets a [[PowerUp Super Mushroom]]]]

A very specific type of superpower. The character has the ability to change their size. Usually, this starts off one way, such as only being able to [[IncredibleShrinkingMan shrink]] or [[AttackOfThe50FootWhatever grow]]. Eventually, this starts to seem a little lame (unless the change comes with added SuperStrength, or other RequiredSecondaryPowers in order to offset that pesky SquareCubeLaw), and they probably end up being able to do both with an upgrade of some sort, or a HandWave about training.

In the case where outfits don't follow suit with the character, most particularly in shrinking, it's likely to cause ShapeshiftingExcludesClothing. Also, don't even try to think about [[ShapeshifterBaggage those pesky conservation laws]], they don't exist, as far as Sizeshifters are concerned.

Compare MakeMyMonsterGrow, where a character makes a monster grow to great heights.
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!!Examples

[[foldercontrol]]

[[folder:Anime & Manga]]
* ''Manga/FairyTail'' has Guild Master [[CoolOldGuy Makarov]], who is one of the strongest characters in the series, if not the strongest himself. Usually, though, he is a [[MiniatureSeniorCitizens Miniature Senior Citizen]].
** Panther Lily can temporarily shift back into the regular body he had back in Edolas for battles. In Earthland, he's just as small and cute as any other Exceed.
* The three main characters in ''Ultimate Girls'' have the ability to grow to 100 feet tall.
* Kirara of ''InuYasha'' can alternate between her housecat-sized form and her battle-ready form, which is roughly the size of a horse.
* A power of the ''{{Guyver}}'' Gigantic, growing into the massive Gigantic Exceed. Useful when one of your enemies turns into a {{Kaiju}}. It's implied that not only does it increase the Guyver's physical size but also increases the power of the Giga-Smasher and the Gravity Orb. To the point where Sho considered using gravity orb to create a small black hole (an extremely difficult and almost uncontrollable feat when previously done by Guyot) to be the ''less'' destructive option than the Giga-Smasher Exceed!
* ''Anime/MazingerZ'': Several Mechanical Beasts had the ability to changing size. The first of them -Bicong O9- showed up as soon as episode 12.
** ''Anime/GreatMazinger'': Marquis Yanus could change size, although she and her HumongousMecha became smaller instead of bigger, since she was a spy and by dwarfing her mecha to human size she could blend in with the humans.
* Employed by the Akimichi clan in ''{{Naruto}}'' as part of their clan jutsu, being able to increase the size of their whole body or just specific parts (usually their arms or chest). Choza is the first one to turn into a giant onscreen [[spoiler:and has spent most of the ninja war fighting in this form]], and Choji uses it a couple of times as well.
* Piccolo from ''Manga/DragonBall'' has this ability as an extension of his RubberMan power, though he only used it once against Goku in the original ''DB'', and then against Garlic Junior in ''Z'' filler. Lord Slug, being a recycled King Piccolo with some Piccolo Jr thrown in, grows gigantic at the climax of his movie (Piccolo, sadly, does not).
* Two filler characters have this ability in ''OnePiece'', both of them giants who ate the Mini Mini no Mi fruit, which gave them the ability to shrink at will. One, Blyue, only appeared in a game, while the other, Lily Enstomach, appeared in the Z's Ambition filler arc of the anime.
* In ''MagicalGirlLyricalNanohaVivid'', [[spoiler:one of Fabian's devils]] has the ability to grow big enough [[SwallowedWhole to swallow multiple mages whole at the same time]].
[[/folder]]

[[folder:Comics -- Books]]
* ComicBook/AntMan and company (Black Goliath, [[ComicBook/YoungAvengers Stature]], Wasp, and Yellow Jacket) of Comicbook/TheAvengers. Started out only being able to shrink. Later gained growth powers.
** The original Ant-Man, Hank Pym, invented [[AppliedPhlebotinum Pym Particles]] which enable this exact power, and allow anyone who can get their hands on them to use it. Said particles were used, among other things, to create a super-villain prison where all the villains were 6 inches tall. [[CardboardPrison Needless to say, there was a breakout.]]
* Short-lived ''Comicbook/{{Excalibur}}'' member Micromax.
* TheAtom of the ''JusticeLeagueOfAmerica''. Since the power comes from his belts, anyone who gets their hands on one can use it, much like the Pym Particles. As a consequence, there have been a few successors to the name, as well as an EvilCounterpart, Dwarfstar.
** DC's original shrinking guy, Doll Man, had the not-too-impressive ability to shrink to about six inches... though he retains his full-sized weight and mass, resulting in a measure of super strength. There's a modern Doll Man, as well, but he's permanently tiny.
** The Atom is an impressive version of this power set. Rather than gaining the ability to grow, he eventually gained the ability to shrink down to subatomic levels, opening up possibilities available to almost no one else. In addition, he can alter his molecular density, which enables him to glide on a low setting or have the equivalent strength of his regular size on a high one.
** Another member of the Atom legacy, Atom Smasher of the JusticeSocietyOfAmerica, has the ability to grow. Unlike the Pym Particles, this is accomplished by his bones and muscles actually breaking and reforming as he enlarges. He also can't grow much larger than two or three times his original size.
* Colossal Boy and Shrinking Violet of the ''ComicBook/{{Legion of Super-Heroes}}''. In the '90s version of the team, Colossal Boy died and Violet gained his growing powers, rechristening herself [=LeViathan=]. In the '00s version, Colossal Boy lives and Vi has been renamed Atom Girl.
** In the Threeboot ('00s) version, Colossal Boy prefers to be known as "Micro Lad", as his ''actual'' ability is to shrink to human size from his normal sixty-foot-tall size.
* Titan from ''Comicbook/JusticeMachine.''
* Elasti-Girl of the ''Comicbook/DoomPatrol''.
* Among villains, one of the best known examples is Giganta from the {{DCU}}. However, she didn't develop this ability until she appeared in ''WesternAnimation/SuperFriends'', making the current version of her something of a CanonImmigrant.
* Alice from ''[[Literature/AliceInWonderland Alice's Adventures in Wonderland]]'', in the ''LeagueOfExtraordinaryGentlemen'', retained her size-changing powers from the infamous scene in the children's book.
* Micro-Might from ''{{PS238}}''. Shrinking means her body increases in density, increasing her strength and durability. However, if she gets ''too'' dense, she's unable to move.
* In ''{{Wildguard}}'', Jack Giant and Blaction Figure had growing and shrinking powers, respectively
* Mighty Man, from ''Amazing Man Comics'', has the ability to change his size.
* Miss America, who was originally created for ''Military Comics'' but later became part of TheDCU, has the power to shrink.
* Mr. Mystic, from ''The Spirit Section'', has the ability to change size.
* Little Cheese, from the AnimalSuperhero team ''Comicbook/CaptainCarrotAndHisAmazingZooCrew'', is anthro mouse who can shrink himself to the size of a real mouse.
* Golden Age supervillain [[YellowPeril the Claw]] could shift between a six-foot tall man and large enough to dwarf New York City.
* Tara and Garganta from ''ComicBook/{{Femforce}}'' both have the ability to grow to giant size.
* Maul from ''ComicBook/WildCATs''.
[[/folder]]

[[folder:Films -- Animated]]
* ''SinbadLegendOfTheSevenSeas'' has [[BigBad Eris, Goddess of Chaos]], able to shift between [[AttackOfThe50FootWhatever normal and absolutely massive with no problem]]. It seems to mostly be for the sake of intimidation and just because she can, as she favors [[BatmanGambit manipulating people based on their flaws]] and sending the occasional minion over stomping on random things herself.
[[/folder]]

[[folder: Literature]]
* {{Piers Anthony}}'s ''A Golem in the Gears'' features a character named Rapunzel who, due to her heritage as the daughter of Jordan the Barbarian and Bluebell Elf, can grow or shrink to any size she wants.
[[/folder]]

[[folder:Live-Action TV]]
* Most heroes of the ''Franchise/UltraSeries''. As well as the ''Franchise/{{Godzilla}}'' franchise's CaptainErsatz of Series/{{Ultraman}}, [[Film/GodzillaVsMegalon Jet Jaguar]].
* Justin Stewart of ''Series/PowerRangersTurbo'', a ten-year-old ChildProdigy who was the blue ranger, shifted to adult size when he morphed for [[StockFootage some reason]]. He shifted back whenever he removed his helmet, oddly enough. It was almost like he could only maintain his shifted size in situations where he'd be played by a stunt double.
* The ''Series/MisfitsOfScience'' had Dr. Elvin "El" Lincoln a really tall guy who could shrink.
* Crash Mc Larson on ''TheAquabatsSuperShow'' can grow to an enormous size, but it's controlled by his emotions, which he's not very good at controlling, which makes them rather unreliable.
[[/folder]]

[[folder:Tabletop Games]]
* Perhaps needless to say, tabletop [=RPGs=] created to handle playing in the superhero genre usually include both powers. Fights between characters of massively disparate sizes can also seriously challenge a game's usual combat rules, which usually assume roughly human-sized opponents facing each other as the unspoken default and whose designers may not have stopped to consider how to address questions such as "can I climb/fly into my giant-sized opponent's ear and knock him out from there?"
* ''TabletopGame/DungeonsAndDragons''
** The wizard spells [[http://www.d20srd.org/srd/spells/EnlargePerson.htm Enlarge Person]] and [[http://www.d20srd.org/srd/spells/ReducePerson.htm Reduce Person]], which [[ExactlyWhatItSaysOnTheTin do exactly what it says on the tin]]. Also [[http://www.d20srd.org/srd/spells/RighteousMight.htm Righteous Might]] for clerics.
** Originally introduced in the 1st Edition ''Oriental Adventures'' sourcebook (and then seen again in ''Complete Arcane'') are the Giant Size and Minute Form spells. Even a SquishyWizard is going to hurt when she's hitting you with a ''tree''.
** Psionic characters have the [[http://www.d20srd.org/srd/psionic/powers/expansion.htm Expansion]] power, which achieves the same effect. It has the added bonus of working on non-humanoids just as effectively as humanoids and even allowing the target to grow even more. There is, of course, an opposite that causes the target to reduce in size.
** The race of spriggans from early editions of the game were gnome-sized normally, but could grow to the size of ogres as a racial ability.
* In ''TabletopGame/ChangelingTheLost'', there exists a Kith (sub-type) of the Ogres known as [[OurGiantsAreBigger Gargantuans]]; their particular gift as Changelings is called Spurious Stature, which enables them to grow to enormous size for a brief time. Given the somewhat more subdued nature of the New World of Darkness, this is less extreme than most examples of this type, though a newly escaped Gargantuan can grow to the size of a gorilla or grizzly bear depending on their power. Supplementary material implies that their size-changing power is a consequence of their reduced power on Earth; supposedly, some Gargantuans remember being of perpetual giant-size in the domain of the Fae.
** The multi-kith rules also make it possible for other sorts of Ogres to do this as well, or any possible Changeling, depending on what's house-ruled in.
[[/folder]]

[[folder:Theater]]
* Clarence Willard of Ripley's ''Believe It or Not'' stage show could somehow shift his body so that he appeared to grow several inches.
[[/folder]]

[[folder:Toys]]
* Toa Bomonga and Toa Norik of ''Franchise/{{Bionicle}}'' fame wear a [[MaskOfPower Mask of Growth and Mask of Diminishment]], respectively.
[[/folder]]

[[folder:Video Games]]
* ''Franchise/SuperMarioBros''
** Mario, of course. Firstly he had the Super Mushrooms that made him grow. Then in ''VideoGame/NewSuperMarioBros'' a Mini Mushroom was introduced which shrunk him to fit into tiny spaces and WalkOnWater, as well as a Mega Mushroom which made him even bigger than with the Super Mushroom.
** Although ''VideoGame/NewSuperMarioBros'' series seems to continue the adjustment first seen in ''VideoGame/SuperMarioBros2'', that the "big" size is actually the standard; Mario and friends shrink when they get hit and then need to use a Super Mushroom to return to normal.
** [[BigBad Bowser]] had occasionally became a giant in some games, and [[VideoGame/SuperMarioGalaxy Rosalina]] actually has the ability to grow to the size of a planet!
** ''VideoGame/WarioLand'''s Wario, in symmetry with his redder counterpart -- but he also loses most of his hair when he shrinks.
** King Boo, as of ''VideoGame/LuigisMansionDarkMoon'', gained this ability. Unlike most others in the series, it seems he can use it at will.
** In the ''VideoGame/PaperMario'' games -- well, the first two -- both Mario and enemies can grow, increasing their Attack. Some enemies have attacks that shrink Mario and/or his partner, reducing their Attack.
*** In ''VideoGame/SuperPaperMario'', the Starman makes the character who touches it change to his/her 8-bit version and grow to almost the height of the screen, temporarily allowing you to plow through enemies and breakable blocks.
* ''Videogame/{{Touhou}}'': Suika Ibuki's most famous use of her density manipulation comes in the form of her 'Missing Purple Power' spellcard, which causes her to roughly triple her size. {{Fanon}} depictions sometimes show her becoming a literal [[AttackOfThe50FootWhatever 50-foot oni]] and beyond. What makes this even more noticeable is the fact that Suika is one of the shortest characters in the series at normal size. She also has the shrinking variation: She can generate mini-Suikas which are roughly 3 inches tall.
** Also from Touhou, Shinmyoumaru is an exclusive example of this. However, she doesn't just make herself bigger. [[OhCrap She makes her bullets AND THE PLAYER bigger, too.]] Very bad in a game in which you have to dodge bullets.
* In ''Super {{Pac-Man}}'', Pac-Man could eat a Super dot and temporarily become enormous. The super-sized Pac-Man was much faster and could pass through locked doors and ghosts without a problem.
* In [[Videogame/TheLegendOfZeldaTheMinishCap The Legend of Zelda: The Minish Cap]], Ezlo's magic enables Link to shrink down to mouse-size.
* AsurasWrath has Asura's Master, Augus, who has a blade that has this power.
** [[FatBastard Wyzen]] is this as well.
* ''VideoGame/StarGladiator'''s Gore Gajah and Luca are able to either grow or shrink through the use of Plasma Magic.
* In ''VideoGame/AliceInWonderland'' for the Commodore64, Alice can shrink and grow using consumable mushrooms that respawn every once in a while.
* By contrast, in ''VideoGame/AliceMadnessReturns'', once Alice finds a pool of liquid, she can change to a smaller size as long as you hold LB. This has several benefits: The ability to get through keyholes, the ability to see clues left by the Insane Children, the ability to (better) see (nearly) invisible platforms and Snouts, the ability to escape certain attacks, and the ability to heal in Shrinking Violets (or, in a NewGamePlus, heal even without them as long as you're wearing the Classic costume). In Queensland, she eats some cake in order to grow, after which she's able to crush the Executioner, then go on through a sequence involving the ripping of tentacles, the squashing of hearts, and the elimination of [[MookMaker hundreds]] of now-relatively-tiny Card Guards. After squashing the last heart, she drinks from what is essentially a bowl to her, then shrinks, stepping over the wall as she does.
[[/folder]]

[[folder:Web Comics]]
* Durkon from ''Webcomic/TheOrderOfTheStick'' occasionally transforms into a [[http://www.giantitp.com/comics/oots0111.html fifteen-foot-tall dwarf]] when in dire straits. (Based on ''D&D'' spell Righteous Might, see above.)
* Vittoria of ''{{SERGOM}}'' can do this.
* Boltrin of ''DragonMail'' can grow once per day.
* Saurus from ''Webcomic/{{Zodiac}}'' has this ability.
[[/folder]]

[[folder:Web Original]]
* In the ''Literature/WhateleyUniverse'', not only are there many people who can do this, but there is more than one superpower that will let you do it. Some Warpers can shrink or grow by using a warp displacement field about themselves so that they don't change but their relationship to the outside world is altered. Some Shapeshifters can shrink or grow also, and ''they'' have the MagicPants problem.
* In ''Literature/{{Worm}}'', identical twins Menja and Fenja have this ability.
[[/folder]]

[[folder:Western Animation]]
* Apache Chief from ''WesternAnimation/{{Superfriends}}''. Considering he's wearing a loincloth, we hope he's wearing some undies.
** His {{DCAU}} {{Expy}} Longshadow has the same power, but is sensible enough to wear pants.
** Apache Chief's powers were also [[FreudWasRight analyzed]] in an episode of ''HarveyBirdmanAttorneyAtLaw''.
* Although they don't grow themselves, these are primarily the abilities of ''WesternAnimation/{{Ben 10}}'s'' aliens Grey Matter (little guy) and Waybig (very... well, guess yourself). Later, an alien called Humongosaur is added with regular growing powers. Still later, the shrinking Nanomech becomes available. While Waybig is much bigger and stronger than Humongosaur even at maximum growth, Humongosaur gets much more use even when both are available on account of Waybig being the size of a skyscraper and thus physically unable to fit in many places Ben where has to fight.
* Big purple Mego of ''WesternAnimation/KimPossible'' -- "[[StealthPun He's a shrinker]]."
* Bumblebee's animated version on ''WesternAnimation/TeenTitans''.
* ''WesternAnimation/XiaolinShowdown''
** The Changing Chopsticks shrink any user to the size of a rice. And if used with the Reversing Mirror they actually make the user grow.
** Not to mention Dojo has this power all the time.
* ''WesternAnimation/DextersLaboratory''
** Capital G of the Justice Friends could use this power. Only seen twice, neither time helpful.
** One episode involved Dexter having to watch over his sister's imaginary friend, a jolly dragonish creature named Koosalagoopagoop (or Koosy for short) who can change size at will.
* Ickis of ''AaahhRealMonsters'' is normally a little UglyCute [[KillerRabbit bunny-like]] monster, but can balloon up to an impressive height when scaring humans.
* Jake from ''WesternAnimation/AdventureTime'' can grow more than ten times his size, as well as shrink down to pocket size. It helps that he's also a RubberMan.
* Meteor Man from ''[[http://en.wikipedia.org/wiki/Birdman_and_the_Galaxy_Trio The Galaxy Trio]]''.
* A number of Transformers from ''TransformersGenerationOne'' change size when they transform, most famously Megatron (Walther P-38) and Soundwave (tape player).
** This has carried on to other ''Transformers'' series, the most notable between ''WesternAnimation/TransformersAnimated'' and ''WesternAnimation/TransformersPrime'' with characters like Prowl, Bulkhead, and Arcee.
** Also in ''Animated'', Shockwave can change size even while in the same form. [[spoiler:This is part of disguise as an Autobot, because Autobots are on average much smaller than Decepticons in ''Animated''.]]
* From ''WesternAnimation/TheSuper6'' comes Elevator Man, who can grow or shrink when he presses a button on his belt.
* Rubilax from ''WesternAnimation/{{Wakfu}}'' is tiny in his default (true) form, but the more he is hit the bigger he gets. In season 2 [[spoiler:Anathar copies this power.]]
* Cassie from ''WesternAnimation/DragonTales'' had a tendency to shrink to about a foot tall when upset.
* In ''WesternAnimation/BarbieAndTheSecretDoor'', the more magic Malucia's wand drains, the larger its headpiece becomes.
[[/folder]]
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