DeepL

API

Machine translation API for text and documents

Price: Free credits, then paid
Access: API key

About

DeepL is a machine translation API for text and whole documents, with glossaries, style rules and a text-improvement endpoint. It is for apps that need translation in many languages. The API rejects calls made directly from a browser, so requests must come from a backend.

What you can do with it

Translate text strings into 100+ languages from your app
Translate Word, PowerPoint and PDF files and keep their formatting
Fix grammar and spelling with DeepL Write, and keep glossary terms consistent

Get started

Sign up for a DeepL API plan
Copy your API key from your account page
On a free plan, call api-free.deepl.com instead of api.deepl.com

Example

# On a free API plan, use https://api-free.deepl.com instead
curl -X POST https://api.deepl.com/v2/translate \
  -H "Content-Type: application/json" \
  -H "Authorization: DeepL-Auth-Key $DEEPL_API_KEY" \
  -d '{"text": ["Hello world!"], "target_lang": "DE"}'

Details

Hosting: Hosted service
Available in: Worldwide
Official SDKs: C#, Java, JavaScript/TypeScript, PHP, Python, Ruby
MCP server: Local