Public HTTP Proofreading API

We offer a simple HTTPS REST-style service that anybody can use to check texts with LanguageTool. The only public endpoint is the following one - do not send your requests to any other endpoints you might find in the homepage's HTML code or elsewhere:

https://languagetool.org/api/v2/check

When using it, please keep the following rules in mind:

  • Do not send automated requests. For that, set up your own instance of LanguageTool or get an account for Enterprise use.
  • Only send POST requests, not GET requests.
  • Access is currently limited to:
      • 20 requests per IP per minute (this is supposed to be a peak value - don't constantly send this many requests or we would have to block you)
      • 75KB text per IP per minute
      • 20KB text per request
      • Only up to 30 misspelled words will have suggestions.
      • These limits may change anytime.
  • Only HTTPS is supported, not HTTP.
  • This is a free service, thus there are no guarantees about performance or availability.
  • The LanguageTool version installed may be the latest official release or some snapshot. We will simply deploy new versions, thus the behavior might change without any warning.
  • Read our privacy policy to see how we handle your texts. You are responsible for giving your users information about how their data is handled.
  • We expect you to add a link back to https://languagetool.org that's clearly visible.

API documentation

See the JSON API.

If you want to use the HTTP API from Java (e.g. because this needs less memory than using the classes directly), try RemoteLanguageTool.

Libraries to simplify usage

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