Free APIs

Free Translation & language APIs

Translation, dictionaries and grammar checks. 8 APIs with a usable free tier, checked on their official docs on 2026-10-08.
8

Neural machine translation, 100+ languages

Free tier
First 500,000 characters/month free
Auth
OAuth
Docs
docs

Catch: Needs a billing-enabled Google Cloud project

source

Text translation and transliteration

Free tier
Free F0 tier: 2 million characters/month
Auth
API key
Docs
docs

Catch: Requires an Azure account

source

Open-source machine translation API

Free tier
Open source and free to self-host
Auth
API key
Docs
docs

Catch: Hosted API needs a paid key; self-host for free

source

Translation memory and machine translation

Free tier
Free; anonymous use is limited to 5,000 chars/day
Auth
No key
Docs
docs

Catch: Daily character caps; register an email for more

source

Grammar and spell checking

Free tier
Free public API with per-IP limits
Auth
No key
Docs
docs

Catch: Free limits are low; premium for more

source

English word definitions, phonetics and audio

Free tier
Free, no key
Auth
No key
Docs
docs

Catch: English only; community-run

Word finding: rhymes, synonyms, autocomplete

Free tier
Free, no key until 1 Feb 2027, then a free key is required
Auth
No key
Docs
docs

Catch: From 1 Feb 2027 limited to 100,000 requests/day per key

Dictionary and thesaurus data

Free tier
Free key for non-commercial use
Auth
API key
Docs
docs

Catch: Non-commercial; attribution required

source

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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