Starting a long anime series is very different from watching a typical 12- or 24-episode show. Some anime franchises have been running for decades, while others continue to add new episodes faster than many fans can keep up with. Finishing them requires real commitment, making them as much a hobby as a form of entertainment.
The anime on this list are not ranked because they are difficult to watch or because they overstay their welcome. Many are widely regarded as some of the greatest anime series ever made and have built loyal fan bases across multiple generations. Instead, they are ranked by the sheer amount of time and dedication required to experience their stories from beginning to end. If you’re ready to take on an anime marathon, here are the 19 long-running anime series that take the longest to finish in 2026.
1. One Piece
With more than 1,160 episodes released by 2026, One Piece remains the longest ongoing story on this list and shows no signs of slowing down. Since its debut in 1999, the series has followed Monkey D. Luffy and the Straw Hat Pirates across an ever-expanding world filled with unforgettable characters, massive battles, and interconnected story arcs.
One of the biggest changes in 2026 is the anime’s move to a seasonal release schedule. Instead of producing episodes almost every week throughout the year, Toei Animation has shifted to shorter seasonal releases. This approach gives the production team more time to maintain animation quality while staying closer to Eiichiro Oda’s manga. The ongoing Elbaph Arc is adapting the source material at a much faster pace without unnecessary filler episodes.
Although One Piece has an intimidating episode count, surprisingly little of it is filler compared to many other long-running shonen anime. Most episodes contribute directly to the main storyline, making the series feel like one continuous adventure rather than a collection of unrelated arcs.
Another reason this is an excellent time to begin watching is that the story has officially entered its Final Saga. After more than two decades of world-building, the anime is finally moving toward its long-awaited finale.
2. Detective Conan (Case Closed)
Detective Conan has entertained mystery fans since 1996 and continues to rank among the longest-running anime ever produced. By 2026, the series had surpassed 1,200 episodes while continuing to release new mysteries on a regular basis. Despite its enormous size, it remains surprisingly accessible because most episodes tell self-contained detective stories.
The series follows teenage detective Shinichi Kudo after a mysterious poison transforms him into a child. Living under the name Conan Edogawa, he secretly solves criminal cases while searching for the organization responsible for his condition. Every investigation introduces clever puzzles, memorable suspects, and a satisfying end that make the show easy to enjoy even without watching every previous episode.
Recent developments have also rewarded longtime viewers. The central mystery has continued to evolve instead of remaining completely static, giving fans new reasons to stay invested after nearly three decades. Whether you choose to experience every mystery or only the essential episodes, Detective Conan remains one of the biggest viewing commitments in anime history.
3. Naruto, Naruto Shippuden, and Boruto
Few anime franchises have influenced modern shonen as much as Naruto. Across Naruto, Naruto Shippuden, and Boruto: Naruto Next Generations, the franchise has grown beyond 1,000 episodes, making it one of the largest anime universes ever created.
The original Naruto introduces viewers to Naruto Uzumaki and his dream of becoming Hokage. Shippuden expands the story into a global conflict filled with powerful villains, emotional character development, and some of anime’s most memorable battles. Boruto later shifts the focus to the next generation while continuing the legacy of the Hidden Leaf Village.
For years, one of the biggest criticisms of the franchise was its heavy reliance on filler content, particularly during Boruto. However, the future of the anime looks very different. Studio Pierrot is preparing a new adaptation of Boruto: Two Blue Vortex with a seasonal production model that aims to stay much closer to the manga. This change should significantly reduce filler episodes while improving animation quality.
4. Pokémon
Pokémon is one of the few anime franchises that has successfully entertained multiple generations of viewers. Since premiering in 1997, the series has grown to more than 1,300 episodes and nearly 25 animated movies. What began as Ash Ketchum’s journey to become a Pokémon Master has now evolved into a new era with Pokémon Horizons introducing a fresh cast of protagonists.
Unlike many long-running anime, Pokémon is designed around shorter adventures that rarely require extensive knowledge of previous episodes. Most stories focus on individual journeys, battles, and new Pokémon encounters.
However, completing the franchise from beginning to end is still a massive challenge. Watching every television episode alongside the movies represents one of the largest anime marathons available. Even though each episode is relatively easy to follow, the sheer volume of content requires months of dedicated viewing.
5. Dragon Ball Franchise
Very few anime have shaped the shonen genre as much as Dragon Ball. Created by Akira Toriyama, the franchise has inspired generations of manga artists and remains one of the most influential action series ever produced. Across Dragon Ball, Dragon Ball Z, Dragon Ball GT, Dragon Ball Super, and Dragon Ball DAIMA, the franchise now includes nearly 660 television episodes, with numerous movies and specials expanding the universe even further.
Although Dragon Ball spans multiple decades, the franchise is organized into separate series rather than one uninterrupted storyline. This approach allows viewers to experience each chapter of Goku’s adventure at a more manageable pace. Every series expands the story with new rivals, greater challenges, and iconic transformations while continuing the evolution of one of anime’s most recognizable heroes.
The franchise is famous for its legendary battles, iconic villains, and constant evolution of power levels. From early martial arts tournaments to universe-threatening conflicts, Dragon Ball has consistently raised the stakes of its action while maintaining its adventurous spirit.
Even after decades of success, Dragon Ball continues to attract new audiences through fresh anime projects and modern adaptations. While its total watch time is shorter than some entries on this list, completing every series still requires a significant commitment.
6. Bleach
Bleach remains one of the most influential shonen anime ever created, and 2026 marks a major milestone for the franchise. After the original television series ended in 2012, before adapting the manga’s final storyline, the anime returned with Bleach: Thousand Year Blood War. The final installment, The Calamity, is expected to conclude Ichigo Kurosaki’s story, bringing one of anime’s biggest franchises to its long-awaited ending.
When all television series are combined, Bleach will surpass 500 episodes. While that may sound intimidating, it is one of the easiest long-running shonen anime to binge because it contains significantly less filler than many of its competitors. Most episodes contribute directly to the main story, allowing viewers to experience the narrative without skipping large portions of the series.
The return of Bleach has also revived interest in the legendary Big Three era alongside One Piece and Naruto. For the first time in many years, all three franchises are once again releasing major anime content, giving longtime fans and newcomers an exciting opportunity to revisit these iconic series together. With its stylish action, memorable characters, and emotional storytelling, Bleach continues to be one of the most rewarding long anime to complete.
7. Doraemon
Doraemon has entertained families for generations and remains one of Japan’s most beloved anime franchises. The current television series began in 2005 and has already surpassed 1,400 episodes. When earlier adaptations from the 1970s and 1980s are included, the franchise has been on television for more than five decades.
The story follows Nobita, an ordinary boy who receives help from Doraemon, a robotic cat sent from the future. Every episode introduces creative gadgets that often lead to humorous situations and valuable life lessons. Because each adventure stands on its own, viewers can start almost anywhere without feeling lost.
Watching every Doraemon episode is a huge undertaking, but the series is designed to be enjoyed gradually. Its timeless humor, family-friendly storytelling, and simple adventures have allowed it to remain popular with children and adults for decades, making it one of the longest-running anime ever produced.
8. Crayon Shin chan
Since its debut in 1992, Crayon Shin Chan has grown into one of Japan’s longest-running comedy anime. With well over 1,200 episodes, the series has entertained viewers through its playful humor, memorable characters, and everyday family adventures centered around the mischievous Shinnosuke Nohara.
For many viewers, Crayon Shin-chan is easy to enjoy because each episode stands on its own. Rather than following a long, interconnected plot, the series centers on Shin-chan’s everyday adventures at school, at home, and around his neighborhood. His mischievous behavior creates the comedy, and most stories are resolved within a single episode. As a result, newcomers can start almost anywhere in the series and enjoy it immediately without needing background knowledge or worrying about missed story developments.
Its episodic structure is one of the biggest reasons the series has remained successful for more than three decades. Writers can constantly create fresh situations without needing major story arcs or dramatic cliffhangers.
Although the anime is famous for its comedy, it also includes heartfelt moments that celebrate family life and childhood. That balance has helped Crayon Shin-chan become a cultural icon in Japan while continuing to attract new audiences around the world.
9. Sazae san
No anime comes close to matching the incredible longevity of Sazae-san. First broadcast in 1969, the series has continued for decades and now includes around 9,000 episodes. This remarkable achievement has earned it the Guinness World Record as the longest-running animated television series in history.
Rather than telling a story, each episode consists of several short family-focused segments. These everyday adventures follow Sazae and her family as they experience ordinary life, making the series easy to enjoy without watching previous episodes.
For many years, Sazae-san remained largely unavailable outside Japan, making it difficult for international anime fans to experience this historic series. Recent efforts to expand its accessibility have introduced more viewers to one of Japan’s most enduring cultural icons.
Because of its enormous episode count, very few people attempt to watch every installment from beginning to end. Instead, the series is best enjoyed the same way Japanese audiences have experienced it for generations, as a relaxing weekly tradition rather than a marathon viewing project.
10. Chibi Maruko chan
Chibi Maruko-chan has remained one of Japan’s most beloved anime since its television debut in 1990. Although the series experienced a short break during the 1990s, it quickly returned and has now surpassed 1,100 episodes, making it one of the country’s longest-running animated shows.
The anime follows the everyday experiences of young Maruko and her family as they navigate school, friendships, and ordinary childhood adventures. Instead of dramatic conflicts or high-stakes battles, the series focuses on relatable situations that viewers of all ages can appreciate.
Each episode tells a complete story, allowing audiences to watch episodes in any order. This format has helped the anime remain fresh for decades while making it easy for new viewers to join at any point.
The gentle humor, nostalgic atmosphere, and charming characters have made Chibi Maruko-chan a favorite among Japanese families. It’s simple storytelling demonstrates that an anime does not need epic battles or complex plots to build a lasting legacy.
11. Ojarumaru
Ojarumaru may not receive as much international attention as other long-running anime, but its episode count is truly remarkable. Since premiering in 1998 on NHK, the series has produced well over 1,800 episodes.
The story follows a young prince from the Heian period who unexpectedly finds himself living in modern Japan. His daily adventures are filled with gentle comedy, imaginative situations, and valuable lessons designed for younger audiences.
Episodes are short and self-contained, making the anime easy to watch without following a larger storyline. This simple format has allowed the series to release new episodes almost every year while maintaining its popularity among children and families.
Although it remains relatively unknown outside Japan, Ojarumaru has quietly become one of the country’s greatest television success stories and deserves recognition among the longest anime series ever created.
12. Yu-Gi-Oh! Franchise
The Yu-Gi-Oh! franchise has remained one of the most successful anime based on a trading card game for more than two decades. Across series such as Yu-Gi-Oh!, GX, 5D’s, ZEXAL, ARC-V, VRAINS, SEVENS, and GO RUSH!!, the franchise has accumulated hundreds of episodes while introducing new characters, worlds, and duel mechanics.
Despite its long history, Yu-Gi-Oh! is surprisingly approachable for new viewers. Instead of continuing a single narrative across every installment, the franchise refreshes itself with a new protagonist, setting, and story in each major series. This format allows fans to start with the series that interests them most while still enjoying exciting card duels, evolving strategies, and unforgettable rivalries that have defined the franchise for decades.
13. Fairy Tail
Fairy Tail has become one of the most popular fantasy shonen anime thanks to its memorable guild members, exciting battles, and strong focus on friendship. Including the original series and Fairy Tail: 100 Years Quest, the franchise now exceeds 300 television episodes while continuing the adventures of Natsu, Lucy, Happy, and the rest of the Fairy Tail guild.
The anime combines action, humor, emotional moments, and magical battles without becoming difficult for newcomers to follow. Each major arc introduces fresh villains, unique locations, and stronger enemies while steadily developing the main cast.
14. Chiikawa
Chiikawa proves that episode length does not always determine how large an anime becomes. Since premiering in 2022, the series has released well over 350 episodes despite each installment lasting only a few minutes. Frequent releases have allowed the franchise to grow at an impressive pace in a remarkably short period.
The anime follows a lovable group of small creatures as they navigate everyday challenges through gentle comedy, friendship, and surprisingly emotional moments. Its charming animation and relaxing atmosphere have helped it become one of Japan’s fastest-growing modern anime franchises.
The franchise continues to expand through new episodes, merchandise, and theatrical projects, demonstrating how successful short-form anime has become in recent years. Chiikawa is a perfect example of how consistent releases can quickly create one of the largest modern anime libraries.
15. Sgt. Frog
Sgt. Frog, also known as Keroro Gunso, is one of anime’s most entertaining long-running comedy series. Across 358 episodes, the story follows Sergeant Keroro and his alien squad as they repeatedly attempt to conquer Earth. Their hilarious plans almost always fail, leading to countless memorable adventures filled with slapstick humor and pop culture references.
Rather than following a continuous storyline, Sgt. Frog builds its humor through self-contained episodes that place the characters in a different comedic scenario each time. This episodic format makes the series highly accessible, allowing new viewers to start watching from almost any episode without needing prior knowledge of the plot or characters.
The show’s creative humor appeals to both younger audiences and longtime anime fans thanks to its clever parodies of science fiction, giant robots, and classic anime tropes. Even after hundreds of episodes, the writers continue to find new ways to keep the comedy fresh.
16. Gintama
Gintama is often considered one of anime’s greatest comedy series, but it is much more than a collection of jokes. Across more than 360 episodes, the anime balances outrageous humor with emotional storytelling, unforgettable characters, and intense action arcs that rank among the best in shonen anime.
The series follows Gintoki Sakata and his friends as they accept odd jobs in a version of Edo that has been transformed by alien invaders. While many episodes focus on comedy, the story regularly shifts into serious conflicts that reveal deeper character development and larger threats.
This balance makes Gintama different from purely episodic comedy anime. Although some comedic episodes can be watched independently, major story arcs build upon earlier events, rewarding viewers who experience the series in order.
17. Yo Kai Watch Franchise
The Yo Kai Watch franchise has grown into one of the largest monster-collecting anime series outside Pokémon. Across its main series and several spin-offs, the franchise now includes more than 460 episodes featuring supernatural creatures inspired by Japanese folklore.
The story follows young protagonists who gain the ability to see Yo Kai, mysterious spirits responsible for many strange events in everyday life. Every episode introduces new creatures, humorous adventures, and imaginative situations that keep the series fun for viewers of all ages.
The combination of colorful animation, family-friendly storytelling, and creative monster designs has helped Yo Kai Watch remain popular for years. While finishing every episode still takes considerable time, the relaxed viewing experience makes the journey much less demanding than many action-focused anime.
18. KochiKame
KochiKame is one of Japan’s longest-running comedy anime and remains a landmark television series despite being less familiar to international audiences. Running from 1996 to 2016, the anime produced 373 episodes centered on the daily adventures of police officer Kankichi Ryotsu and his coworkers.
Instead of following a dramatic storyline, the series focuses on workplace comedy, humorous misunderstandings, and changing trends in Japanese society. Its stories reflect everyday life across several decades, giving viewers a unique look at how Japan evolved during the anime’s long broadcast.
With hundreds of episodes spanning twenty years, KochiKame stands as one of anime’s greatest examples of long-running comedy television. It continues to hold an important place in anime history because of its remarkable consistency and lasting popularity.
19. Inuyasha
Inuyasha remains one of the defining fantasy anime of the early 2000s. Combining the original television series with Inuyasha: The Final Act brings the complete story to 193 episodes. While it is shorter than many other anime on this list, it still represents a significant viewing commitment for new fans.
The story follows Kagome and the half-demon Inuyasha as they search for the scattered shards of the Sacred Jewel while battling dangerous enemies across feudal Japan. Its blend of action, romance, comedy, and supernatural adventure helped make it one of the era’s most successful anime.
The original television series often slowed its pacing because it caught up with the manga, resulting in longer story progression across several arcs. Years later, The Final Act adapted the remaining manga chapters at a much faster pace, delivering a satisfying end to the story.
