Short-Runner television Anime running 10-14 episodes (generally 12). They're usually scheduled for a 3-month airing slot, if aired weekly, at Otaku O'Clock.note Anime with this format are commonly called '1-cour' shows, with a 24-26 episode run being called a '2-cour' show and so on; 'cour' (kuuru/クール) being a jargon term (probably from the French cours) used in the Japanese broadcasting industry referring to the periods of time these shows are aired and scheduled, as detailed in the above "note".
This format became popular (see 12 and 13
) in the second half of the 2000s as a compromise to the often sporadic nature of OVAs and the longer, sometimes filler-ridden, previous standard of 22-24 episodes. Being a smaller time investment and financial risk, it is much easier to determine if a show will be successful; or, if it isn't, to not take on as much of a loss. In that respect, the closest Western equivalent to this trope would be Front 13, Back 9.
It's also common for seasons to have 13 episodes produced, broadcasting only 12 of them, and leaving the 13th as a Bonus Episode OVA. This is especially common in shows that frequently dance the line with controversial, taboo, and/or explicit Fanservice scenes. In this case, whatever the creative team wanted to do that just wouldn't bypass the Moral Watchdogs is saved for here.
The only real downside to this format is the possibility of a Gecko Ending, as most anime released each season are adaptations of manga or light novels, many of which are still ongoing at the time of airing.
Due to their length, a particularly noteworthy 12-episode anime can often lead to severe cases of Awesomeness Withdrawal.
For the British equivalent, see British Brevity.
- .hack//Legend of the Twilight Bracelet is 12 episodes long, but was also an adaptation of a monthly serial.
- 91 Days, plus a pseudo-prequel OVA episode that expands on character backstories.
- Absolute Duo
- Aesthetica of a Rogue Hero (also has 6 specials that are 4 minutes each)
- Akane-iro ni Somaru Saka, plus an OVA
- Akuma no Riddle, plus an OVA.
- And You Thought There is Never a Girl Online?
- Another: It has 12 episodes, but also has a (somewhat spoiler-filled) OVA which even uses the same opening and ending credits. Since it chronologically happens before and during the events of the first episode, it could in some regards also be looked at as a 13-episode anime.
- Amnesia: Memories
- Angolmois
- Anne Happy
- Antique Bakery
- Arcana Famiglia, with an extra OVA.
- Aria the Scarlet Ammo, plus an OVA
- Arte
- Assassins Pride
- Babylon
- B Gata H Kei (Yamada's First Time)
- Barakamon
- Ben-To
- Berserk (2016)
- Black Blood Brothers
- Black Lagoon had two seasons of this kind, the second called "The Second Barrage".
- BlazBlue: Alter Memory
- Blend-S
- Blessing of the Campanella, plus an OVA.
- Blood-C
- Bludgeoning Angel Dokuro-chan: Eight episodes at first, then four more.
- Blue Spring Ride
- BNA: Brand New Animal
- Boogiepop Phantom
- Cat God
- Cat Planet Cuties, plus an OVA
- Chaos Dragon
- Chivalry of a Failed Knight
- Chaos;Head
- Cowboy Bebop in its initial airing was 12 stand-alone episodes and a filler "recap" episode, due to it being too violent for its time slot. The rest of the series was made at the time, but they decided to leave out the more violent episodes for the first run.
- Cube×Cursed×Curious
- Daily Lives of High School Boys
- Dancougar Nova: The last half especially feels very rushed and underdeveloped.
- Dance in the Vampire Bund
- Danganronpa 3: Future Arc was 12 episodes, while the concurrently aired Despair Arc was 11 episodes, with the Hope Arc special serving as the finale of both and airing as the twelfth episode of Despair.
- Darker Than Black's second season fits, but not the first season and its 24 episodes.
- Deadman Wonderland
- Death Parade
- Destiny of the Shrine Maiden, and quite a few other works originally created by Kaishaku, for example:
- Magical Meow Meow Taruto
- Both UFO Ultramaiden Valkyrie TV series.
- Shattered Angels
- Devil May Cry: The Animated Series
- Devils' Line plus an OVA episode.
- Dimension W
- Domestic Girlfriend
- Dorohedoro, though its second Blu-ray will include another six OVA episodes.
- Dragon Crisis!
- DRAMAtical Murder, plus an OVA adapting the Visual Novel's bad endings.
- Dusk Maiden of Amnesia
- ef - a tale of memories and its sequel ef. A Tale of Melodies
- El Hazard: The Alternative World
- ERASED
- Fortune Arterial: Akai Yakusoku
- Yoake Mae Yori Ruri Iro Na ~Crescent Love~ is an earlier example of one of August's Visual Novels adapted into a 12-Episode Anime.
- Full Metal Panic? Fumoffu had 12 episodes produced, with several split into two half-episodes. Two half-episodes were pulled from broadcast due to a kidnapping plot that had parallels in Real Life at the time.
- Full Metal Panic!: Invisible Victory
- Freezing plus two OVA episodes.
- Futakoi Alternative and its predecessor Futakoi.
- Gabriel DropOut
- Ga-Rei -Zero-
- Gatchaman Crowds plus a 13th episode that is a finished version of the 12th.
- Girlish Number
- Girly Air Force
- Gokujo
- Grand Blue
- Grenadier
- Green Green, plus a hentai OVA which was excluded from the English dub.
- Grimgar of Fantasy and Ash
- Ground Control to Psychoelectric Girl
- Gugure! Kokkuri-san plus six 5-minute special episodes.
- The "La Verite" remake of Hanaukyō Maid Team has 12 episodes.
- Hanayamata
- Hand Shakers
- Heaven's Memo Pad
- He Is My Master (No sequel series yet)
- The Hero is Overpowered but Overly Cautious
- Hi-Speed Jecy is a 12-episode OVA split across six volumes.
- All four seasons of Hidamari Sketch: the first has 12, the second has 13, the third and fourth 12 again. However, between the DVD-only bonus episodes, and some TV specials broadcast some months after the main series run, the totals are 14 per season (or 16 for the third season if one counts the TV specials as part of it).
- Highschool of the Dead plus an OVA episode.
- Himouto! Umaru-chan
- Hitohira
- How to Raise a Boring Girlfriend plus an OVA episode.
- Innocent Venus: unfortunately, because of some bad pacing, the middle was painfully slow while the later episodes felt too rushed.
- Iron Man
- Is This a Zombie? plus one OVA episode.
- Izetta: The Last Witch
- Joker Game plus two unaired episodes bundled with the Blu-ray releases.
- Kabaneri of the Iron Fortress
- Kaguya-sama: Love Is War
- Kaiba
- Kamen no Maid Guy has one 12-episode season so far, but there's rumors of another one following soon.
- Kandagawa Jet Girls
- Kashimashi: Girl Meets Girl
- Katanagatari has twelve episodes, but each episode is fifty minutes long and was aired monthly rather than weekly.
- Keijo!!!!!!!!
- Kids on the Slope
- Kiniro Mosaic
- Kiss Him, Not Me
- Kotoura-san
- Kure Nai
- Kurozuka
- Laughing Under the Clouds
- Legend of Himiko
- Let's Go! Tamagotchi might count as one.
- Loveless. The manga has 9 volumes, still ongoing.
- Magical Girl Lyrical Nanoha ViVid, in comparison to the first two seasons (13 episodes) and the third season (26 episodes).
- Magical Girl Spec-Ops Asuka
- The Magnificent Kotobuki
- Mahoromatic got 12; its sequel series (subtitled Something More Beautiful) got 14.
- Makai Senki Disgaea, the anime based loosely on the game.
- Manabi Straight! plus an OVA, which takes place between the 6th and 7th episodes, to make this series 13 episodes when counted.
- Marginal #4 Kiss Kara Tsukuru Big Bang
- MariaHolic
- Matoi the Sacred Slayer
- MM!
- Mobile Suit Gundam: The 08th MS Team, although the twelfth episode at least feels closer to an OVA sequel episode than a series finale.
- Mob Psycho 100 (season 1)
- Mononoke
- Monster Musume, plus an OVA.
- Monthly Girls' Nozaki-kun plus six 3-minute special episodes.
- My Roommate is a Cat
- Najica Blitz Tactics
- Nanatsuiro Drops
- Nerima Daikon Brothers
- New Game!
- Nightwalker: A unique case, as the first four episodes were originally released as an OVA series. The following eight episodes were then aired as a television series.
- Ninja Nonsense
- No Matter How I Look at It, It's You Guys' Fault I'm Not Popular! (a.k.a. Watamote) plus an OVA.
- One-Punch Man had 12 full episodes, with a few OVAs aired after the end of the season.
- One Week Friends received a 12-episode anime, with special mini-episodes released on the DVD sets.
- Ore wo Suki Nano wa Omae Dake Ka Yo received a 12-episode anime adaptation covering the first 4 volumes of the light novel series, with an OVA release the following year (one that was postponed by the COVID-19 pandemic) to adapt the fifth volume.
- Please Teacher! and Please Twins! are twelve episode animes, with one-episode OVAs each.
- Paradise Kiss
- Pilot Candidate, though it got a thirteenth episode OVA that never made it out of Japan.
- Potemayo
- Power Rangers Dino Force Brave is a Korean rare live-action example, just like Akibaranger under 13-Episode series. Justified since it only runs for nearly 15 minutes per episode.
- The Price of Smiles
- Princess Princess ran for 12 episodes following three of the five volumes of manga. No word yet on whether the manga sequel, Princess Princess Plus will be getting an anime adaptation.
- Princess Principal
- Prism Ark
- The Promised Neverland
- Puella Magi Madoka Magica
- Punch Line
- Queen's Blade
- The Quintessential Quintuplets
- Rage of Bahamut: Genesis
- Ranpo Kitan: Game of Laplace
- RDG: Red Data Girl
- Revisions
- RideBack
- Rocket Girls
- Rozen Maiden and its sequel series, Rozen Maiden Traumend.
- Sacred Seven
- Say I Love You
- School Days had 12 episodes and two OVA releases.
- selector infected WIXOSS
- Sengoku Basara's first two seasons, including a pair of OVAs.
- Seraphim Call makes good use of this format, devoting one episode to each of its 11 central characters and having them all meet in the last one.
- School Days, along with two OVAs
- Shimoneta, plus an OVA
- Shingetsutan Tsukihime
- Show by Rock!!
- Sing "Yesterday" for Me
- So, I Can't Play H! plus an OVA.
- Sola
- Someday's Dreamers
- Someday's Dreamers II: Sora
- Sound of the Sky
- Special 7: Special Crime Investigation Unit
- Sunday Without God: Plus a bonus unaired 13th episode.
- Sword Art Online: Alternative Gun Gale Online
- Taisho Baseball Girls
- Tamako Market and received a movie sequel, Tamako Love Story.
- Tenrou Sirius the Jaeger
- Togainu no Chi
- Tsuritama
- Ultraman Neos: 12 episodes plus a special OVA.
- Umi Monogatari
- Uta Kata, which also had a postlude OVA.
- Venus Versus Virus had 12 episodes...but ended on a cliffhanger.
- Waiting in the Summer had 12 episodes and an OVA episode.
- Wandering Son. It's a 12-Episode Anime, with only eleven episodes being broadcast on television and one unreleased one being added onto the Blu-Ray.
- WATATEN!: an Angel Flew Down to Me
- Wave, Listen to Me!
- When Supernatural Battles Became Commonplace
- Wolverine
- WorldEnd: What Do You Do at the End of the World? Are You Busy? Will You Save Us?
- The World God Only Knows had two seasons 12 episodes long each.
- The World is Still Beautiful
- Xenosaga: The Animation
- Valkyrie Drive: Mermaid
- Yamada-kun and the Seven Witches. The part of the manga it covers is 90 chapters long, leading to rather mixed reactions by those who had already read the manga. Especially the last half is noteworthily rushed, while the first half is more faithful to the manga.
- Yami to Boushi to Hon no Tabibito
- Yosuga no Sora
- Yumeria
- Anohana: The Flower We Saw That Day
- Bunny Drop
- [C] - The Money and Soul of Possibility
- Eden of the East: 11 episodes and two movies.
- Fractale
- Galilei Donna
- Genji Monogatari Sennenki
- given: 11 episodes, followed by a movie.
- Hand Maid May (one of the earliest examples, first aired in 2000)
- Hakaba Kitarō
- Ingress
- Jyu-Oh-Sei
- Kämpfer is an odd case; it's 12 episodes, but it's basically an 11-episode series with episode 12 being a fanservicey, non-continuity bonus episode that's aired after the ending such as it is.
- The Millionaire Detective - Balance: UNLIMITED
- Moyashimon
- No6
- Ping Pong
- Princess Jellyfish, although the extremely open-ended "finale" leaves a lot of plot threads unresolved.
- Ranpo Kitan: Game of Laplace, but the extremely open-ended "finale" leaves a lot of plot threads unresolved.
- Psycho-Pass (season 2)
- Silver Spoon has two 11-episode seasons.
- Sweet Blue Flowers
- The Tatami Galaxy
- Tokyo Magnitude 8.0
- Trapeze
- Ultraman Ginga: 11 episodes and two movies.
- Wandering Son
- Wotakoi: Love is Hard for Otaku
- Zankyou no Terror
- Zombie Loan plus two DVD episodes.
- Aggretsuko (2018)
- Backstreet Girls
- Big Order
- Black Butler: Book of Circus
- Blood Lad
- Coffin Princess Chaika (season 2)
- Date A Live (season 2)
- Dazzle
- DEVILMAN crybaby
- Haikyuu!! (season 3)
- Inari, Konkon, Koi Iroha
- Kono Subarashii Sekai Ni Shukufuku O! (both seasons + 2 OVAs)
- My First Girlfriend is a Gal (plus one OVA)
- My Mental Choices Are Completely Interfering with My School Romantic Comedy
- Mysteria Friends
- Piano
- Problem Children Are Coming from Another World, Aren't They?
- Rilakkuma and Kaoru
- The Testament of Sister New Devil (season 2)
- Triage X
- AIR TV: though it had 13 episodes, the last was a Recap Episode and generally discounted.
- The Recap Episode wasn't even included in the Funimation English DVD release.
- There are also two OVA episodes called AIR in Summer.
- Akane-iro ni Somaru Saka — thirteen episodes plus a Fanservice OAV.
- Amagami SS — The second season, Amagami SS+ Plus, has thirteen episodes.
- Angel Beats!, which was supposed to have 26 episodes and was unexpectedly cut down to 13. A bonus OVA was released later, and the disk set came with an unaired Bizarro Episode.
- Appare-Ranman!
- Baccano! got 13, although episodes 14-16 were released later as bonus material.
- Baka and Test: Summon the Beasts ran for two seasons, and each season contained 13 episodes.
- Bananya
- Blue Drop
- Bottle Fairy
- Buddy Complex
- Canaan
- Cells at Work!
- The Monkey Punch anime Cinderella Boy. The series ended whilst Ranma/Rella's daily "Freaky Friday" Flip still wasn't resolved and originally suggested an upcoming new season. Unfortunately, the high cost caused the series to be put to a premature end.
- Danganronpa: The Animation, which suits the series just fine.
- Descendants of Darkness
- The original series Deep Love was thirteen episodes, while the spin-off Deep Love ~Host~ ran for twelve.
- The anime of Devil Survivor 2
- Divergence Eve has two thirteen-episode seasons.
- Earth Maiden Arjuna
- Elfen Lied is a Thirteen Episode Anime, plus the 14th DVD-only episode.
- Figure 17 Tsubasa & Hikaru has 13 episodes, but is somewhat unique in that each episode is 45 minutes long, and one episode was shown each month during its first airing. As such, the anime takes significantly more time exploring and developing its characters, has a gentler pace, and animation and art that's practically OVA quality.
- It was later rebroadcast as a standard 26 episode show, with each episode cut in half.
- Flag
- Full Metal Panic! The Second Raid had 13 episodes, with a separate 30 minute OAV produced afterwards.
- Gargantia on the Verdurous Planet
- Glasslip
- Gravitation, 13, cut so heavily it would need a sequel series to bridge the gap to the manga's sequel series...
- Gunslinger Girl, with 13 episodes and a 13-episode sequel, as well as a 2-episode OVA.
- Happy Happy Clover had a total of 13 episodes made in 2007 which adapted the first three volumes.
- Haibane Renmei, written by Lain's character designer Yoshitoshi ABe, is also a 13-episode series.
- Hanebad!
- Hellsing got 13 episodes. All funding was cut around episode 10-11, and they had just enough to wrap up the series in the next two-three episodes.
- Hikonin Sentai Akibaranger is a rare live action example. Interestingly, it was originally supposed to be a one season show with twelve episodes, but the budget increased for one more episode. Then, a second season was made that also lasted thirteen episodes.
- Hyakko has 13 episodes and a short 12-minute-long OVA.
- I Can't Understand What My Husband Is Saying has two thirteen episode seasons.
- Il Sole penetra le illusioni: Plus an unaired 14th episode that serves as a prequel.
- Is It Wrong to Try to Pick Up Girls in a Dungeon? with an OVA episode.
- Jubei-chan: Secret of the Lovely Eyepatch and the second season Counter Attack of the Siberia Yagyu.
- K
- Kannagi: Crazy Shrine Maidens
- The first Kanon TV adaptation is 13 episodes long plus a special. The KyoAni remake was a full season with 24 episodes.
- Kazemakase Tsukikage Ran
- Key the Metal Idol — though it came out as a total of 15 episodes: 13 regular, plus two "movies".
- Android Kikaider: The Animation has 13 episodes once "recap episode" #8 is added in. However, this episode was not shown during Kikaider's Adult Swim run, nor was it put onto DVD.
- The TV series is followed up by a 4-episode OVA, loosely based on the Kikaider 01 tokusatsu series.
- Kino's Journey is another 13-episode series.
- Kokoro Library
- Legends Of The Dark Kings (aka Ten no Haoh), a 13-episode anime adaptation of a manga spinoff of Fist of the North Star that centers around Raoh.
- Love Lab
- Lupin III: The Woman Called Fujiko Mine (the "12th" episode is a two-parter, making 13 episodes in total)
- Magical Girl Lyrical Nanoha and its sequel series Magical Girl Lyrical Nanoha A's compacted 26 episodes of plot into 13 high-pressure episodes; however, Magical Girl Lyrical Nanoha StrikerS was the standard length (and pace) of a 26 episode series.
- Mayoi Neko Overrun! has twelve episodes plus a metafictional thirteenth episode of the characters doing commentary on the series.
- Megalo Box
- Metal Fighter Miku
- Mezzo DSA
- Midori Days got 13 episodes (which is probably why two major characters from the manga, Lucy and Nao, were left out).
- The Misfit of Demon King Academy
- Miss Kobayashi's Dragon Maid had 13 episodes plus an OVA and 7 DVD mini-episodes.
- Mobile Suit Gundam 0083: Stardust Memory
- Mob Psycho 100 (season 2)
- My Teen Romantic Comedy SNAFU and its sequel have 13 episodes, each season also have an OVA episode.
- Myself ; Yourself
- Niea_7
- Neo Angelique: The Anime of the Game Spin-Off is two sets of 13 episodes.
- Now and Then, Here and There
- Occult Academy
- Oku-sama wa Mahou Shoujo
- Oreshura
- Panty & Stocking with Garterbelt, though Studio Gainax apparently has a second season planned, although it's very unlikely to happen as the series creator left Gainax to create Studio Trigger.
- Dual! Parallel Trouble Adventure has thirteen episodes, plus a special OVA.
- Paranoia Agent
- Please Teacher!
- Prétear
- Princess Connect! Re:Dive
- Psychic Detective Yakumo
- Rascal Does Not Dream of Bunny Girl Senpai
- Sands of Destruction
- Saishuu Heiki Kanojo (Saikano / She, the Ultimate Weapon)
- Serial Experiments Lain, true to its indie nature, is a thirteen-episode series.
- Servant × Service
- Shadow Star got 13 episodes.
- Stitch & Ai is a Chinese variant of this trope. Only one thirteen-episode season was produced and released, which aired with a Mandarin Chinese dub (the show was originally produced in English with American animators assisting) from March 27 to April 6, 2017. The original English version aired in Southeast Asia throughout the month of February 2018. It later received a free digital streaming release in the United States on December 1, 2018, albeit with the show's ninth episode remaining unreleased there.
- Submarine Super 99
- Shouwa Genroku Rakugo Shinjuu, with the first being a retelling of the OVAs. The OVAs cover the first volume. The anime's two seasons cover all 10 volumes of the manga.
- The Silver Brumby's only season had 13 episodes.
- Space Patrol Luluco: Ran for 13 episodes during the Spring 2016 season, which were idiosyncratically divided into four "seasons" of three episodes each, plus "season final" consisting of just the 13th episode.
- Spice and Wolf had 13 episodes, with the 7th episode being DVD-only. The second season had 12 episodes, with an epilogue to the last season as an episode 0 on DVD.
- Starship Operators
- Str.A.In.: Strategic Armored Infantry
- Stratos 4 has 13 episodes in its first season. Its second season has 6 episodes plus a 2-episode OVA, and there is another intermediary two-part OVA.
- To Heart
- To Heart 2 as well, however, it has a three part OVA, and a two part OVA spinoff To Heart 2: Another Days, which is loosely based on the Gaiden Game spinoff of the same title.
- Tokkô
- Tona-Gura! has 13 episodes with a semi-firm conclusion. That said, the manga is still ongoing, and whether or not this conclusion is used remains up in the air. Up until 2009, manga chapters tended to be fully fleshed, expanded versions of the anime episodes.
- Tsurune, plus one OVA.
- Violet Evergarden, plus one OVA and two movies.
- Whispered Words
- White Album and its sequel, White Album 2, who have 13 episodes.
- Windy Tales
- WORKING!!
- Birdy the Mighty Decode got 13 episodes; its second season got 12 (but with bonus episode #13 produced shortly after.... which technically acts as original episode 1).
- Haganai started with 12 episodes in fall 2011, then got another 12-episode season in winter 2013.
- The Familiar of Zero started with 13 episodes, and has three sequel seasons with 12 each.
- Gravion had 13 episodes with little to no conclusion. All of them are wrapped up nicely in the 12 episodes sequel Gravion Zwei. There were plans for a 3rd season, but since most plot elements have been concluded, they decided to turn it into Dancougar Nova instead.
- I Can't Understand What My Husband Is Saying and it even lampshades how most anime only run for 12/13 episodes and Hajime admits he's always curious on how it goes on with the heroes after, during its own 13th Episode. Then the anime got a second season
right after this episode.
- Ikkitousen's first season had 13 episodes. It later got another three seasons of 12 episodes each.
- Infinite Stratos has two 12-episode seasons, not counting the OVA.
- KoihimeMusou. All 3 seasons have 12 episodes.
- Love, Chunibyo & Other Delusions. (Both seasons contain 12 episodes plus an OVA. Given their plot importance, they could be seen as 13 ep. seasons.) note
- Maria Watches Over Us has three 13-episode seasons.
- The initial run of The Melancholy Of Haruhi Suzumiya got 14. The second season also has 14 episodes (a total run of 28, including the first season).
- One of the first season's episodes is the Non-Indicative First Episode, which is a "movie" created by the SOS club rather than a normal episode.
- Also consider that 8 of 14 episodes in season two are generally the same.
- The first season of My Hero Academia was 13 episodes, but every subsequent season has had 25 each.
- Oreimo has twelve broadcast episodes in its first season and 13 in its second, plus four OVA episodes.
- Sailor Moon Crystal has ran for three 13-episode seasons, each adapting an arc from the manga.
- All three Sayonara, Zetsubou-Sensei seasons are 12-13 episodes long.
- Strawberry Marshmallow. Two OVA series, one with three episodes, the other with two, were made after the TV series, so there are now 17 episodes of Ichigo Mashimaro.
- Vandread first aired with 13 episodes, but managed to get a second 13 episodes and resolve the story. There's rumors of a third season, but aren't there always?
- Zombie Land Saga originally aired with only 12 episodes, but due to the massive popularity in Japan alongside the show's critical acclaim, a second season was announced in 2019, under a new title: Zombie Land Saga: Revenge.
- Angels of Death's anime adaptation is 16 episodes long.
- ARIA The ANIMATION and The ORIGINATION (Season One and Season Three) are both 13 episodes in length whereas ARIA The NATURAL (Season Two) is 26 episodes long.
- Attack on Titan: Its first season was 25 episodes long, then its second season was 12. The third season is quite unusual: it was 22 episodes in total, but it was split up six months apart into a Part One and Part Two consisting of 12 and 10 episodes, respectively. The fourth and final season was then scheduled for a very odd episode count of 16 episodes.
- Ayakashi: Samurai Horror Tales is an unusual case; it's an 11-episode series and was aired as such on Japanese television, but is actually an anthology consisting of three separate 3- or 4-episode anime by completely different production groups. The final series in the anthology, "Bakeneko", ended up with its own spinoff, Mononoke, also a 12-ep series.
- Bakemonogatari ran for 15 episodes long.
- Nisemonogatari: 11 episodes
- Monogatari Series: Second Season: 26 episodes
- Owarimonogatari: 12 episodes
- While Beyond the Boundary only has one 12-episode season in 2013 with an prequel OVA, it later received two movies, the first one aired in 2014, adapting the anime series; the second one served as a sequel, which aired in 2015. It also had several spinoff shorts.
- Blue Literature follows the same format, with five arcs adapted from Japanese literature.
- The Big O, though notable for being one of the first shows of this type to get a second season, was actually planned as a 26-episode anime, but had production end after only 13 due to low ratings in Japan - the second season, co-produced by Cartoon Network after the show pulled much better ratings abroad, was essentially just bringing the staff back to finish the other half of the original series.
- Black★Rock Shooter is eight episodes long, and was aired in noitaminA. If you count the OVA (which was released two years earlier and is in a separate continuity), then it had nine episodes in total.
- The 2019 adaptation of the Boogiepop Series was 18 episodes long. The series started off with a one-hour special with the first two episodes debuting immediately, and then in a truly unique situation, episodes 10-13 were all released at once when the show hit that point, leaving enough time for the entire season to finish its run in a standard season.
- Buddy Complex had a first season with 13 episodes. It was slated for a second season, but low ratings caused season 2 to get cut to only two episodes which released as a pair of OVAs.
- As mentioned in the main article, many live-action Western shows are adopting this, such as NBC's Chuck. During the 2007-2008 season, however, a lot of this was the unintentional result of that season's Writer's Strike.
- D.Gray-Man in its first TV broadcast from Oct. 2006 to Sept. 2008 had a whopping 103 episodes. The odd thing is that the show is considered to be 2 seasons of 51 and 52 episodes, even though there was no break in the airing schedule and it continuously aired until the end. Regardless, the manga went on hiatus for over 2.5 years before returning in July 2015. A continuation series called D. Gray Man: Hallow aired starting July 2016 and picked up where the first anime left off, but Hallow was only 13 episodes long.
- The first arc of Dragon Ball had its 23 chapters into 13 episodes, with some chapters being expanded to fill an entire episode while several others were consolidated into one. Presumably this was done to fit this trope on the off-chance that the anime didn't catch on. Needless to say, it did.
- Digimon Adventure was written so that it could end cleanly after 13 episodes. It didn't have to, and ultimately ran to 54 episodes, and seven more seasons followed after that.
- Durarara!! in its initial run had 24 episodes, divided into two halves and denoted by the different opening and closing credits sequences. For its second run, it had 36 episodes which were divided into three cours. Unlike the first run where both cours were broadcast back-to-back, the new cours were released separately - Shou was in Winter 2015, Ten was in Summer 2015, Ketsu was in Winter 2016.
- Fate/Zero's first season has 13 episodes, but it's effectively 14 episodes, because the first episode is 45 minutes long. This was apparently done to get the humongous amount of prologue exposition (for a show which is itself a prologue for an entire franchise) out of the way in the first episode. The second season is a normal 12-episode season.
- ufotable's next Fate adaptation, Fate/stay night [Unlimited Blade Works], is an even crazier case. The first season is 12 episodes, but it's actually 16 episodes long because there was a prologue "Episode 0" that was 45 minutes long, and Episodes 1 and 12 were also double-length episodes. The second season was 13 episodes, all standard length this time.
- Fate/kaleid liner PRISMA☆ILLYA, a spinoff series of the above-mentioned Fate franchise, started its anime adaptation with a 10 episode season. Then the second season got split into two cours, each one 10 episodes long. The third season is 12 episodes long.
- The first season of Food Wars! was 24 episodes long. The second season, Ni no Sara, was only 13 episodes long, much to the fanbase's irritation because the manga has plenty more content that could easily be adapted. The third season, San no Sara, went back to 24 episodes, but it was a split-cour season divided into two 12-episode airings in Fall 2017 and Spring 2018. The fourth season, Shin no Sara, was 12 episodes in Fall 2019. The fifth and final season, Gou no Sara, was 13 episodes in Summer 2020.
- Girls Frontline's anime adaptations are 12 episodes each, but there's two sets of them which aired sequentially - the "Healing Chapter", which tells original stories, and the "Madness Chapter", which adapts yonkoma chapters from the game's loading screens and the comics purchased with in-game currency - and the episodes are only three minutes long.
- Haikyuu!!'s first two seasons were 25 episodes long each along with a 2 episode OVA. The third season is only 10 episodes long.
- Idolish 7 conveniently has 17 episodes that covers Part 1 of the Main Story
- Kamichu! had 12 to start, with four DVD-only episodes interspersed between the broadcast episodes. (A ploy to get people to buy the DVDs, as the DVD-only episodes are not strictly filler.)
- K-On!'s first two arcs are only twelve episodes, but the show ended with a special episode outside of the second arc. Then it skyrocketed in popularity, and the second season got 26 episodes.
- Kokoro Connect has 13 episodes, but with 4 OVAs on the way in 2013, it's an amount of 17 episodes altogether.
- Little Busters! had a 26-episode first season covering Komari, Mio, Haruka, and Kud's routes along with most of the common route, and then a 13-episode second season covering Kurugaya's route, Rin's route, and Refrain.
- Magical Pokaan ran for 12 episodes, albeit in Two-Shorts format, and with the DVD releases adding three more OVA episodes.
- Princess Tutu was a VERY odd variation on this in its original TV broadcast. The first 13 episodes of the series were the standard 30 minutes each, but a time-slot change beginning with episode 14 lead to the running time being halved and the latter half of the series airing as 24 episodes of 15 minutes each - until the final episode, which was again 30 minutes long. Even more strange is that there was no gap in airing between the "seasons" - the 15-minute episode 14 aired the week after the full-length 13. Confused yet? The DVD release restored the split episodes into 30-minute ones, making it look like a 26-episode series to those who don't know its broadcast history. Of course, there were also the three TV specials produced...
- Psycho-Pass, as far as its regular TV broadcasts went, started off with a 22-episode first season. The second season was 11 episodes long. The third season was only 8 episodes, but in a rather unique case, each episode was double-length (45 minutes long), effectively making it the equivalent of a 16-episode season. Season 3 then had the sequel movie Psycho-Pass 3: First Inspector as its conclusion, which was over 2 and a quarter hours long, which essentially made Season 3 have a runtime equivalent to 22 episodes, the same as the first season.
- Shrine of the Morning Mist has 26 episodes, but each is under a quarter of an hour long, half the "standard" episode length.
- The same goes for the Galaxy Angel anime.
- And Steel Angel Kurumi
- Same goes for Cromartie High School, though they generally broadcast them in pairs.
- As well as Risky Safety, but it has 24 episodes.
- W~Wish and Final Approach each have 13 twelve-minute episodes, aired side-by-side during the "Princess Hour."
- The fourth season of Slayers ending up being split into two 13-episode seasons instead of one 26-episode season. Of course, Revolution leaves a lot of plot threads for Evolution-R to pick up, but season five did get a new OP and ED...
- This isn't too dissimilar to how previous series of Slayers played out: typically, The Dragon would be fought by Episode 13, and from episode 14 onwards, the focus would shift to The Man Behind the Man or some other Big Bad therein.
- It has, however, been packaged together in Japan and elsewhere, and is often referred to as Revolution-R for simplicity's sake.
- Space Dandy consists of two 13-episode seasons, although this had been planned out before it began airing, so it can also be considered a 26 episode series with a break in the middle. Nonetheless, it's still officially two seasons.
- Tokusatsu GaGaGa only ran for seven episodes.
- The second season of Yuki Yuna is a Hero is broken down into two six-episode series Washio Sumi Chapter (which was originally three theatrical films) and Hero Chapter.