Best Grammar Checkers for Chrome

Updated October 2026

How to choose a grammar checker extension

All eight picks catch grammar and spelling mistakes as you type. Most have a free plan with limits and paid plans on top, and LanguageTool's extension needs a paid plan. The real differences are what else they do, which languages they cover and how they handle your account and text.

• Fixing errors or rewriting. Grammarly, LanguageTool and Ginger focus on flagging mistakes. Wordtune and QuillBot lead with paraphrasing and rewriting.
• Languages. LanguageTool checks 25+ languages, but its extension needs a paid plan. Grammarly also gives suggestions in some languages besides English; check its languages page.
• Depth of feedback. ProWritingAid adds 25+ writing reports on readability, repeated words and pacing. Grammarly adds tone and clarity suggestions.
• Account and data control. LanguageTool's core engine is open source with a self-hosting option, but its browser extension needs a paid plan. Harper says it does all of its work offline, and its docs say it is free to use.
• Team messaging. Sapling adds autocomplete for repetitive messages and has a Google Workspace add-on.

Our picks at a glance

Comparisons and alternatives

• Grammarly alternatives: grammar checkers with no account, open source or more languages

Which is the best grammar checker extension for Chrome?

For most people, Grammarly is the best grammar checker extension for Chrome. It checks grammar, spelling and punctuation as you write and suggests tone and clarity fixes. It has a free plan and a paid Pro plan, and it asks you to sign in. It sends your text to its servers, so read its privacy notes first.

Compare Grammarly with LanguageTool or ProWritingAid before you pay for a plan.

What is a good free alternative to Grammarly?

Harper is the free option on this list. Its docs say it is free to use, it is open source and it works offline, though it is built for English. Wordtune and QuillBot have free plans with limits. LanguageTool is free on its website, but its browser extension needs a paid plan.

Which grammar checker gives you the most control over your text?

LanguageTool gives you the most control over where text is processed. Its core engine is open source, so you can run your own server, though the Premium features are not in that version. The browser extension itself needs a paid plan. None of the other picks here list a self-hosting option.

Which grammar checker works in languages other than English?

LanguageTool checks grammar and style in 25+ languages, including variants of English and German, but its browser extension needs a paid plan. Grammarly says it also gives suggestions in languages besides English; check its languages page for the current list. QuillBot says its grammar checker covers 6+ languages.

Which grammar checker is best for long-form writing?

ProWritingAid is built for editing your own long drafts. Its 25+ reports look at the whole text, not only single errors, and its extension page names Google Docs, Notion, Atticus and Campfire. The free plan limits document length, so check the vendor’s current limits before you paste in a chapter.

Which grammar checker works offline?

Harper. Its docs say it does all of its work offline and is free to use, and its code is public on GitHub. It is built for English, and it asks for access to every page so it can check text anywhere. The offline claim is the developer's own, so read its privacy policy before relying on it.

Also see: Best Chrome extensions for students and Best Chrome extensions for creators.