head to head
Grammarly vs LanguageTool
LanguageTool is the open source alternative to Grammarly — ai writing assistant and grammar checker. Here is the honest comparison.
Yes — LanguageTool is a viable free replacement for Grammarly. LanguageTool is open source under LGPL-2.1, written in Java, with 15,042 GitHub stars, 1,581 forks and 2,148 open issues; it was last pushed 8 hours ago. Grammarly costs from $12, while self-hosting LanguageTool carries no licence fee — the trade is your operational time instead of a subscription. 0 other open source Grammarly alternatives are tracked here. Replacement criteria on this page: 4 reasons to move to LanguageTool and 3 reasons to stay on Grammarly.
choose LanguageTool if
- Your Grammarly bill is growing with seats or usage
- You need your data in a format and server you control
- Your compliance posture requires auditing the code that touches sensitive data
- You have (or can rent) a server and basic Docker comfort
stick with Grammarly if
- You need the polished onboarding and support SLAs of a commercial vendor
- Your team has zero capacity to operate software, even self-hosted-simple
- You depend on a Grammarly integration ecosystem that the OSS alternatives have not replicated
Side by side
| LanguageTool (open source) | Grammarly | |
|---|---|---|
| Price | Free (self-hosted) | $12-$15/member/month |
| License | LGPL-2.1 | Proprietary |
| Source code | Public, auditable | Closed |
| Self-hosting | Yes — languagetool-org/languagetool | Cloud only |
| Data ownership | Your server, your format | Vendor's cloud |
| Community | ★ 15K · ⑂ 1.6K | — |
| Built with | Java | — |
Why people look for a Grammarly alternative
About LanguageTool
LanguageTool is open source proofreading software for English, Spanish, French, German, Portuguese, Polish, Dutch, and more than 20 other languages. Its tagline describes it as an AI powered grammar checker for 30+ languages, while the repository description calls it a style and grammar checker for 25+ languages. The project lives in the natural language processing and productivity ecosystem, where it helps writers, editors, and applications detect errors that a simple spell checker cannot find.
read the full LanguageTool overview →
last updated nightly · ranking method: github stars, live-tracked
Frequently asked questions
Is LanguageTool a good replacement for Grammarly?
LanguageTool is an open source alternative to Grammarly (AI writing assistant and grammar checker). It is written in Java and licensed under LGPL-2.1, with 15,042 GitHub stars.
Is LanguageTool free compared to Grammarly?
Yes. LanguageTool is open source — there is no licence fee, and you can self-host it. Grammarly is typically a paid subscription, so the trade-off is licence cost against the operational work of running it yourself.
How do I migrate from Grammarly to LanguageTool?
Migration effort depends on the data formats involved. Check LanguageTool's documentation for import options, and compare the feature table above to confirm the capabilities you depend on are covered before switching.