Looking to replace Grammarly with something free and open-source? These 1 tools are the best open alternatives in 2026 — most are self-hostable, so you keep full control of your data and pay no subscription.

Click a column to sort — the best one depends on what matters to you.
| Alternative | Stars | Language | License | Last commit | In one line |
|---|---|---|---|---|---|
| LanguageTool | — | — | LGPL-2.1 | — | Open-source grammar and style checker, self-hostable. |
Open-source grammar and style checker, self-hostable. Its LGPL-2.1 license keeps the project and its forks open-source forever, and commercial use is allowed. Because it is self-hostable, your data can stay entirely on your own infrastructure.
The top open-source alternative is LanguageTool — Open-source grammar and style checker, self-hostable. The full ranked list is above.
Yes. Every tool listed is open-source and free to use; most can be self-hosted so you keep full control of your data.
Most of these tools are designed to run on your own server or machine, giving you privacy and no subscription fees.
Browse open-source replacements for dozens of popular tools — design, productivity, dev, analytics and more.
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