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Grammar Checker

Catch grammar, spelling and punctuation mistakes in any text.

  • No sign-up required
  • Instant results
  • Nothing is uploaded

Which spelling conventions to check against.

0 words
Checks grammar, spelling and punctuation, and offers a replacement you can apply with one click. British, American and Indian English are all supported, which matters for words like organise and colour. This is the one tool here that sends your text somewhere: checking needs a rule engine far too large to run in a page, so the text goes to LanguageTool's free public service. Do not paste anything confidential into it.

Frequently asked questions

Common questions about the grammar checker.

Where does my text go?+

To api.languagetool.org, the free public endpoint of the open-source LanguageTool project. It is sent from your browser straight to them - this site never sees it - but it does leave your device, which is why you should not paste anything sensitive.

Why did it miss an obvious mistake?+

It works from rules and statistics rather than understanding, so it is strong on spelling, agreement and punctuation and weaker on meaning. “Their going” can slip past where every word is a real word. Treat it as a second pair of eyes, not a proofreader.

Is there a length limit?+

The free service accepts a limited amount per request, so long text is checked in the first 10,000 characters. It is also rate limited: if you check repeatedly you may be asked to wait a minute.

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