TOP Investment Portfolio Mantra Inc.

Mantra Inc.

CEO, Shonosuke Ishiwatari
Mantra Inc.
Delivering manga across language barriers: providing a translation tool specifically for manga with exceptional natural language and image processing technologies


Mantra Inc. makes it its mission to deliver manga across language barriers. It is researching and developing natural language and image processing technologies specifically for manga.
The company leverages these technologies to offer services that break through language barriers and deliver manga to fans around the world.
The cloud-based manga translation tool Mantra Engine, released in 2020, is being used by over 10 partners, including publishers, translation companies and manga distributors. The tool supports the translation of over 20,000 pages (equivalent to around 100 volumes) every month from Japanese to multiple other languages. Not only does it cut back on costs with speedy translations that utilize AI, but it also offers the benefit of allowing official translations to be released quicker than pirated translations, which protects the works and copyrights.
Mantra also worked with Shueisha to release an app called Langaku in 2022, which allows users to learn English while reading manga. On the day of release, the app ranked No. 1 in the education category on the App Store and continues to gain attention as a new language-learning method.


As students in the Graduate School of Information Science and Technology at the University of Tokyo, co-founders Ishiwatari and Hinami won UTokyo1000k, a product idea contest. This led them to start researching and developing machine translation technologies specifically for manga. After earning their doctoral degrees, the co-founders established the company with support from the University of Tokyo FoundX, UTokyo IPC 1stRound, the MITOU Advanced Program and others.


Manga contains many elements that make it difficult to translate, such as the unstructured positioning of drawings and texts, unique colloquial expressions, and complex story-based contexts.
Mantra Inc. developed the world’s most accurate manga machine translation tool to resolve these issues by merging image processing and machine translation technologies designed specifically for manga.
The results have been highly praised by the academic community, such as being featured by AAAI, the top international conference in the artificial intelligence field, and receiving the AAMT Nagao Award from the Asia-Pacific Association for Machine Translation.

7-chōme-3−6 Minamiaoyama, Minamiaoyama HY bldg. 7F (Arai Club), Minato City, Tokyo 107-0062, Japan
Mantra Engine動画


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