Free APIs
Free Translation & language APIs
| API | Free tier | Auth | Docs |
|---|---|---|---|
| Google Cloud Translation Neural machine translation, 100+ languages Catch: Needs a billing-enabled Google Cloud project | First 500,000 characters/month free | OAuth | docs |
| Azure AI Translator Text translation and transliteration Catch: Requires an Azure account | Free F0 tier: 2 million characters/month | API key | docs |
| LibreTranslate Open-source machine translation API Catch: Hosted API needs a paid key; self-host for free | Open source and free to self-host | API key | docs |
| MyMemory Translation API Translation memory and machine translation Catch: Daily character caps; register an email for more | Free; anonymous use is limited to 5,000 chars/day | No key | docs |
| LanguageTool API Grammar and spell checking Catch: Free limits are low; premium for more | Free public API with per-IP limits | No key | docs |
| Free Dictionary API English word definitions, phonetics and audio Catch: English only; community-run | Free, no key | No key | docs |
| Datamuse API Word finding: rhymes, synonyms, autocomplete Catch: From 1 Feb 2027 limited to 100,000 requests/day per key | Free, no key until 1 Feb 2027, then a free key is required | No key | docs |
| Merriam-Webster Dictionary API Dictionary and thesaurus data Catch: Non-commercial; attribution required | Free key for non-commercial use | API key | docs |
FAQ
What is the best free translation & language API?+
Google Cloud Translation, Azure AI Translator, LibreTranslate are good places to start. Compare the free tiers and catches in the table; they differ mostly in limits and whether commercial use is allowed.
Is there a translation & language API without an API key?+
Yes: MyMemory Translation API, LanguageTool API, Free Dictionary API, Datamuse API work without a key.
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