> ## 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 `. 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. # Translating HTML > Learn how to translate HTML content with the DeepL API and exclude specific elements from translation. To translate HTML content, set the `tag_handling` parameter to `html`. The API extracts the text from the HTML structure, translates it, and places the translation back into the structure. Without `tag_handling`, tags are treated as regular text. Set `tag_handling_version` to `v2` to use the improved tag handling algorithm. HTML input is never strictly parsed, so invalid HTML doesn't cause errors in either version. For version details and defaults, see the [`tag_handling_version` parameter](/api-reference/translate/request-translation). ```bash Example request theme={null} curl -X POST https://api.deepl.com/v2/translate \ --header "Content-Type: application/json" \ --header "Authorization: DeepL-Auth-Key $API_KEY" \ --data '{ "text": ["

This is a premium feature.

"], "target_lang": "DE", "tag_handling": "html", "tag_handling_version": "v2" }' ``` ```json Example response theme={null} { "translations": [ { "detected_source_language": "EN", "text": "

Dies ist eine Premium-Funktion.

", "tag_handling_version": "v2" } ] } ``` You don't need to set `split_sentences` for HTML: with `tag_handling=html` it defaults to `nonewlines`, which splits sentences on punctuation only and gives the best translation quality for HTML. To also split sentences on newlines, set `split_sentences=1`. To translate non-HTML XML content, see [Translating XML](/docs/translate/translating-xml). ## Exclude elements from translation To exclude an element from translation, add the `translate="no"` or `class="notranslate"` attribute to it. In the following example, `translate="no"` prevents translation of the paragraph: ```markup Example request theme={null}

My First Heading

My first paragraph.

``` ```markup Example response theme={null}

Meine erste Überschrift

My first paragraph.

```