Japanese LLMs and their applications in business

The market for Japanese large language models has ceased to be a research niche and has entered a phase of real commercialization.

This is evident from three phenomena at once: the Japanese government has begun treating domestic LLMs as an element of state capability, the largest providers are building full implementation offerings, and alongside product models, there is a growing layer of open R&D projects, such as LLM-jp, OpenCALM, or Sarashina.

For business, the most important observation is: "Japanese LLM" does not mean one type of product.

The market coexists with models developed from scratch in Japan, such as tsuzumi and PLaMo, models strongly integrated with enterprise stack and security, such as cotomi, Takane, and Sarashina API, and derivative models that enhance the Japanese language through further training and tuning, such as ELYZA LLM or Rakuten AI 2.0.

Therefore, choosing a model should not start with the question of the highest benchmark, but rather with questions about data, law, deployment environment, integrations, and maintenance cost.

Why is Japan building its own LLMs?

Japan has several reasons for developing domestic models.

The first is language: high-quality handling of the Japanese language requires understanding writing, formal styles, official documents, cultural context, proper nouns, and business customs.