A free web service released on July 6, 2026 by Sakana AI, a Japanese AI company, offering bidirectional translation between Japanese, English, and Chinese. It works with just an account registration and accepts up to roughly 5,000 characters per request. Its defining trait is the concept of “translating Japanese deeply,” powered by Namazu, the company’s own model series tuned for Japanese. It aims to render the parts general-purpose translation tools tend to miss: the sense of distance in business honorifics, culturally rooted expressions, abbreviations, and internet slang. Beyond translation, Proofread and Ask modes share the same screen, so you can ask why a given wording was chosen — something ordinary translation tools do not offer. On August 21, 2026, an update brought a new generation of Namazu.
Key Features
- Translation powered by Namazu, a Japanese-focused model: Rather than a general multilingual model, it uses a model series developed with emphasis on Japanese and the culture and context behind it. Sakana AI announced improved handling of culturally loaded terms such as omiyamairi (a shrine visit for newborns)
- Translate, Proofread, and Ask in one screen: Beyond translating, a Proofread mode polishes your source text into more natural phrasing (with diff highlighting), and an Ask mode lets you follow up on the result — all without leaving the page
- Long inputs up to about 5,000 characters: Paste an entire email or article. Output streams in, so you can start reading before the full text is generated
- Bidirectional Japanese, English, and Chinese: Not just Japanese ⇄ English, but Chinese pairings as well
- Doubles as a dictionary: You can keep asking questions like “why this word?” or “how would you say it more casually?”, which makes it useful for looking up vocabulary and phrasing
- Free with only an account required: As of August 2026, all three functions are free. It runs in the browser with no installation
Pricing
| Plan | Price | What’s included |
|---|---|---|
| Free (account registration) | $0 | Translate, Proofread, and Ask; inputs up to about 5,000 characters |
| API / Enterprise | Not yet available (planned) | Official announcements list file translation, industry-specific models, an API, and enterprise support as future plans |
Pricing is current as of August 2026. Please check the official site for the latest information.
Pros & Cons
✅ Pros
- Focused on rendering Japanese-specific honorifics, cultural terms, and slang, so translations involving Japanese feel less off
- Proofread mode lets you polish your own English or Japanese writing before translating it
- You can ask about the output, checking why a particular phrasing was chosen as you work
- Accepts up to about 5,000 characters at once, and streaming output keeps the wait short
- All features are free to try, so there is little barrier to getting started
⚠️ Cons
- Limited to Japanese, English, and Chinese, so it does not suit multilingual rollouts
- No API as of August 2026, which rules out embedding it in internal systems or apps
- Translating files (PDF, Word, etc.) directly is listed as a future plan; for now you paste the text
- An account is required, so you cannot simply open the URL and start translating
- For business use, review the terms and FAQ on how confidential documents are handled before deciding
Comparison with Similar Services
| Criteria | Sakana Translate | DeepL | Google Translate | ChatGPT |
|---|---|---|---|---|
| Provider | Sakana AI (Japan) | DeepL SE (Germany) | Google (US) | OpenAI (US) |
| Main strength | Japanese honorifics, cultural terms, slang | Natural output, document translation | Breadth of languages, easy and free | Fine-grained control via instructions, versatility |
| Languages | Japanese, English, Chinese | 30+ languages | 100+ languages | General-purpose (multilingual) |
| Input limit | Up to about 5,000 characters | Varies by plan | Varies by plan | Varies by plan and model |
| Proofread / Ask | Proofread and Ask modes | Writing improvement feature | None | Handled through conversation |
| API | Not yet available (planned) | Yes | Yes | Yes |
| Price | Free (account required) | Free tier / paid plans | Free (API is paid) | Free tier / paid plans |
Who Is It For
- Business professionals writing English emails to overseas partners who want to preserve the politeness and social distance of the Japanese original
- PR and marketing staff adapting Japanese articles and materials into English or Chinese
- Language learners who want to understand why a phrasing was chosen rather than just copying the output
- Anyone dissatisfied with how general-purpose tools translate honorifics, proper nouns, and distinctly Japanese turns of phrase
- People who want to compare Japanese translation quality for free before paying for a commercial tool
Summary
Sakana Translate narrows its language coverage to Japanese, English, and Chinese and spends that focus on the hard parts of Japanese: honorifics, cultural terms, and slang. Because Translate, Proofread, and Ask sit in one screen, you can go beyond translating once — polishing the source text or checking the reasoning behind a word choice. That said, an API and file translation are still listed as future plans, so it is not yet suited to system integration or high-volume document processing. A good starting point is to run your own writing through it for free and compare the output with the translation tools you already use.