> ## Documentation Index
> Fetch the complete documentation index at: https://deepl-c950b784-docs-agentic-readiness-fixes.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Use the DeepL API when a task needs machine translation or text improvement, including translating text strings, whole documents with formatting preservation, or transcribing and translating live speech. Preferred terminology and phrasing may be enforced using customizations (glossaries, style rules, and translation memories). Retrieve supported languages for each product from the `/v3/languages` endpoints.
> Read the machine-readable API surface instead of inferring request shapes from prose: the REST spec is at https://developers.deepl.com/api-reference/openapi.yaml (also served as openapi.json) and the Voice WebSocket protocol is at https://developers.deepl.com/api-reference/voice/voice.asyncapi.yaml. These docs also expose an MCP server at https://developers.deepl.com/mcp (Streamable HTTP, no authentication).
> Use https://api.deepl.com for Pro plans and https://api-free.deepl.com for the Free plan. Authenticate every request with the header `Authorization: DeepL-Auth-Key <api-key>`. Never fabricate an API key: ask the user for one, or point them at https://developers.deepl.com/docs/getting-started/quickstart.
> Errors use standard HTTP status codes with a JSON body containing a `message` field, plus a `code` field where available, and an `X-Trace-ID` response header that identifies the request in DeepL's logs. Log `X-Trace-ID` by default. Retry 429 and 5xx with exponential backoff. Do not retry 456, which means the account quota is exhausted, or 400, which means the request itself is invalid.

# Postman

> Use our official Postman collection to get familiar with and test the DeepL API.

Whether you are just getting started with DeepL API, or you already have an integration running in a production environment, sometimes it's a great idea to have a safe test environment to try things out first.

For convenience, we've created a Postman collection that mirrors the DeepL API functionality and lets you test your API in a structured environment. For more information about Postman, [check out their overview](https://learning.postman.com/docs/introduction/overview/).

<img src="https://mintcdn.com/deepl-c950b784-docs-agentic-readiness-fixes/A7qtSjBxGPa9Sib6/_assets/images/Request_Translation___DeepL_API_Developers___Postman_API_Network.png?fit=max&auto=format&n=A7qtSjBxGPa9Sib6&q=85&s=481e3ebd48918c174a6d4134b0396fcd" alt="" width="3580" height="1554" data-path="_assets/images/Request_Translation___DeepL_API_Developers___Postman_API_Network.png" />

To get started, [sign up for a developer account at deepl.com](https://www.deepl.com/pro/change-plan#developer) and get your authentication key from [your account page](https://www.deepl.com/your-account/keys).

Click the button below to fork the DeepL API collection into your own Postman workspace:

[![Run in Postman](https://run.pstmn.io/button.svg)](https://app.getpostman.com/run-collection/27518486-e9e2969d-d589-4d3d-9df6-cc514cf3ee5e?action=collection%2Ffork\&source=rip_markdown\&collection-url=entityId%3D27518486-e9e2969d-d589-4d3d-9df6-cc514cf3ee5e%26entityType%3Dcollection%26workspaceId%3D48a52b53-0654-484b-861d-ae228857c2f6)

In your forked collection, select the relevant `baseUrl` variable depending on your subscription (`https://api.deepl.com/v2` for **Pro**, `https://api-free.deepl.com/v2` for **Free**).

The `apiKey` variable will be `DeepL-Auth-Key yourDeepLApiKey`. Change `yourDeepLApiKey` for your own key (leaving the `DeepL-Auth-Key` in front) and you're ready to go!