The Doraemon franchise have spawned it's share of extended stories and movies, notably the Doraemon's Long Tales series (which dates from 1980 to 2004) and the post-reboot series from 2005 onwards. And a whole lot of these are Adaptation Expansion(s) based on shorts from the manga themselves.
- It dates all the way back to Doraemon: Nobita's Dinosaur, the first feature-length film of the franchise which started as a manga story. The manga ends with Nobita and Doraemon sending Piisuke the dinosaur into the past, before Nobita asks Doraemon for a gadget that allows him to eat carbonara through the nose. The movie continues with Nobita and Doraemon realizing they had sent Piisuke to the wrong era and must travel back in time to retrieve him, only to be ambushed by the Dinosaur Hunters (who doesn't exist in the original story) and Trapped in the Past for the rest of the adventure.
- Doraemon: The Record of Nobita : Spaceblazer have similarities to another short where Nobita and Doraemon explores an alien world, where they discover because of the alien planet's low gravity compared to Earth's they're practically borderline invincible and allowed to perform great feats of strength, at which point they make themselves superheroes to the aliens. The long story however has a Space Western setting, throws in a more powerful villain, a mercenary named Guillermin who eventually considers Nobita a Worthy Opponent, and have Nobita's friends Shizuka, Suneo and Gian thrown into the mix - the latter three pulling a Big Damn Heroes in the final scene to save Nobita and Doraemon who's about to be crushed by Guillermin's mecha.
- The 2009 remake of the above, Doraemon: The New Record of Nobita's Spaceblazer adds even more characters to the roster, including a Canon Foreigner named Morina and Doraemon's sister, Dorami, appearing alongside Nobita's friends to help out in the final battle. Ropporu's father, mentioned to be a Posthumous Character in the original but never appeared physically in the original story, also appears in the remake, during the opening scene and finally revealed to be alive in the ending, to embrace his family after being stranded in another dimension for an unknown amount of time. The henchman Guillermin also pulls a Villain: Exit, Stage Left in the finale only to return to menace the heroes even further, unlike the original who simply passes out after admitting his defeat.
- Doraemon: Nobita and the Steel Troops is adapted from "Let's Assemble a Handmade Robot", both stories starting with Suneo boasting his new, human-sized robot causing Nobita to beg Doraemon into getting him a new robot to compete against Suneo's. Nobita does get a Humongous Mecha in both instances (the original being part of the 22nd-Century Titanic Robo Giant Series purchased by Doraemon, the expansion being a planet-destroying machine from Planet Mechatopia) where the robot parts arrive bit by bit, starting with the legs, torso, and gradually the rest of it's body. The latter however has a Robot Girl spy named Riruru thrown in the mix, and an invading robot army that forms majority of the movie's threat, as well as inclusion of Shizuka convincing Riruru to pull a Heel–Face Turn.
- Doraemon: Nobita and the Birth of Japan is based on a manga short where both stories have the gang deciding to collectively run away from home after constant peer pressure and scoldings from their parents, and decide to spend a week in prehistoric times to avoid the responsibilities of life... only to learn an aesop to value what they already have after stumbling into harshness and loneliness in ancient times. The expansion however has added subplots about warring cavemen tribes, time-traveling criminals intending to change history, and Nobita creating three legendary animals as his pets.
- Doraemon Nobitas Diary Of The Creation Of The World, like the manga short "The Earth Creation Kit", have Nobita literally playing God and creating a brand-new universe with Doraemon's gadgets, before exploring the world he created himself. The film have even more scenes within Nobita's self-created world, however, and it remains intact at the end of the story (unlike the manga short which have the Earth Creation Kit accidentally destroyed when Tamako thought it was trash).
- Doraemon: Nobita and the Galaxy Super-express is adapted from "Milky Way Railroad", where Nobita and friends sneaks off to board a futuristic Galaxy-Faring Space Train after finding leftover tickets in Doraemon's possession. Ironically, the original short have Doraemon strictly forbiding Nobita to use his tickets due to safety concerns (only for Nobita to sneak off with those tickets without Doraemon's permission, like always), but in the expanded story, it's Doraemon himself who invited the gang to come along!
- Doraemon: Nobita and the Windmasters turns a manga short "Typhoon Fuuko", into a feature-length film where the sentient baby typhoon adopted by Nobita (named Fuuko in both instances) turns out to be a Sealed Evil in a Can fated to revive an ancient eldritch monster in destroying humanity. Also absent in the original are a village of Wind-Manipulating wizards in Mongolia, spirits of ancient warlocks, another sentient typhoon named Gorado who's an Evil Counterpart to Fuuko, and yet another time-traveling Omnicidal Maniac criminal who abducts Fuuko to initiate doomsday.
- Doraemon: Nobita in the Wan-Nyan Spacetime Odyssey is based on the manga story "Stray Dog Ichi's Country" with Nobita and friends coming across entire packs of stray cats and dogs, one named Ichi (in both stories) who forms a bond with Nobita. The gang realize there's no place in the present for raising these strays, so they instead send them to ancient times and uses the Evolution Ray to have the animals evolve and adapt on their own. The expanded version have new subplots including a rogue cat named Jara who plots to Take Over the World as retaliation on humanity, the gang spending more time in the past with the evolved cats and dogs, and plenty of action scenes, fights against Jara's minions and a lengthy climax in an amusement park (while the original short contains no action at all since it's a comedic drama).
- The 2007 remake of the 1980s movie, Doraemon: Nobita's Great Adventure into the Underworld is noticeably some 20 minutes longer than the original, and even have a subplot where The Dragon of the film is related to one of the new heroes, Miyuki, a completely new storyline introduced. There are also additional flashbacks for the new characters, including a prologue without the gang in it, something absent in the originals.
- Doraemon: Nobita's Great Adventure in the South Seas expands an anime short based on the manga where Nobita drags Doraemon, Suneo and Gian into a seafaring adventure for Pirate Booty. In the movie version, Shizuka was thrown into the mix as well, before the gang accidentally enters a time warp and into The Golden Age of Piracy where they realize the oceans of the past is infested with Sea Monsters. The movie version even recycles Stock Footage from the anime!
- Doraemon: Nobita and the Green Giant Legend extends an already longer-than-usual manga story, "Goodbye Kibo!" (whose anime counterpart is a two-parter) into a full-length film, with more scenes involving Kibo's fate as an Apocalypse Maiden in terraforming the galaxy. The gang (including Suneo, Gian and Shizuka - opposed to the original where only Doraemon, Nobita and Kibo are involved) also made it to the Plant Aliens' home planet and spends most of the movie in there, something the manga alluded but never really shows.
- Doraemon: Nobita's Great Battle of the Mermaid King is based on "Underwater Pump Simulator", a story where Nobita begs for Doraemon to bring him on a scuba-diving adventure after being envious of Suneo, so Doraemon brings out the titular gadget to summon fishes from the Atlantic into an underwater simulation in Tokyo. The movie however have the gadget summoning a mermaid as well who ends up accidentally stranded in Japan, and the gang's attempts to find the mermaid's home kickstarts the adventure.
- Doraemon: Nobita and the Island of Miracles ~Animal Adventure~ borrows elements from "Long Live the Dodo Bird", where Doraemon and Nobita attempts to rescue extinct, prehistoric animals with the Time Hole. Unlike the manga where the extinct animals are sent to an uninhabited island (and ends right there), the movie have them sending the animals to a 22nd Century animal preserve, the titular Miracle Island, only to contend with poachers from the future intending to enslave the animals with their giant mechas.
- Doraemon: Nobita and The Space Heroes is (rather loosely) expanded from "Special Effects Ultra Dora-Man" where the gang tries making their own toku film using Doraemon's gadgets, with Doraemon insisting that he's cast as the Big Good of the story. And then they stumble into an alien seeking for help to save his home planet, mistaking the gang's film to be real, and kickstarting a whole new adventure.
- Doraemon: Great Adventure in the Antarctic Kachi Kochi have it's first act being based on a manga story where Doraemon and Nobita, intending to escape the summer heat, goes to an uninhabited iceberg in Antartica to create their own mini-wonderland. The similarities end when Nobita found a 100,000-year-old golden bracelet in the ice and realize it's an artifact to prevent an eldritch monster from destroying the world.
- Doraemon: Nobita's Chronicles of the Moon Exploration took the manga short, "Doctrine Association Badges" and recycles it on the moon, with new subplots involving immortal aliens fleeing from the genocidal AI hunting them to extinction added to the mix.
