HTTP

JSON DeepL exposes the same HTTP endpoints its own web tool uses internally to talk to DeepL. On jsondeepl.com they're restricted to trusted callers — same-origin requests made from the jsondeepl.com frontend itself, not from other websites or scripts — to keep hosting costs predictable for a free, unauthenticated tool.

If you self-host your own copy of the project, that same origin restriction applies relative to your domain instead — so these endpoints become a real API for your own frontend to use, no configuration required. To call them directly (from a script, a build pipeline, another service — anything that isn't a browser page load from your own site), set a NUXT_APP_API_KEY env var on your deployment and send it back as the x-app-api-key header on each request.

curl https://your-domain.example/api/translate-text \
  -H "x-app-api-key: $NUXT_APP_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "token": "your-deepl-key", "src_locale": "en", "to_locale": ["de"], "formality": "prefer_less", "text": "Hello world" }'

Nothing else changes either way: you still bring your own DeepL API key per request, and nothing is stored on the server.

Translate a JSON object

Endpoint: POST /api/translate

Body Parameters

type JsonFile = {
  dir_name: string // subdirectory to nest this file's output under, or '' for none
  prefix_name: string // filename prefix, e.g. 'app' -> app.de.json, or '' for none
  json: string // the JSON content to translate, as a string
}

Response

type TranslatedFile = {
  dir_name: string
  filename: string // e.g. 'app.de.json'
  content: string // the translated JSON, stringified
}

Errors

On failure, the response is a standard HTTP error with a JSON body containing statusCode and statusMessage.

Translate plain text

Endpoint: POST /api/translate-text

Body Parameters

Response

// e.g. { "de": "Hallo Welt", "fr": "Bonjour le monde" }

Errors

Same shape and status codes as /api/translate above.