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LanguageTool

★ 13k

Grammar, style and spell checker for 30+ languages; run the server locally and keep your prose private.

LanguageTool does the job of Grammarly and ProWritingAid, self-hosted. It is LGPL-2.1-licensed, a copyleft licence, and setting it up is an afternoon, not a weekend. Grammarly bills $12 for it. 13k stars on GitHub.

Open-source replacement for Grammarly, ProWritingAid.

Licence
LGPL-2.1
Self-hosting
Medium
The paid one costs
$12
GitHub stars
13k
view the code →official site →

Is it actually a replacement?

We have written a verdict on what it replaces — what you lose, and why people still pay:

How LanguageTool runs

Where it runs

LanguageTool runs on your server.

What setup takes

not verified by us yet — check the repo README.

LanguageTool questions

Is LanguageTool open source?

Yes — it is released under LGPL-2.1.

Can LanguageTool replace Grammarly?

Our verdict on Grammarly is YES. Ollama (178k stars), Lobe Chat (65k stars), LibreChat (28k stars) are mature open-source replacements for Grammarly — self-host in one command and stop paying $30/mo.

Can I self-host LanguageTool?

Yes — we rate it medium to self-host, and it runs on your server.

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