1 open source alternatives to Grammarly
AI-powered grammar, spelling, and tone checker. Here are the open source projects real teams use instead — ranked by fit, with honest pros and cons for each.
What people don't love about Grammarly
- Cloud-based — your writing is sent to Grammarly servers.
- Premium features are paywalled aggressively.
- Browser extension can feel invasive.
Current Grammarly pricing (for reference): Free tier; Premium from $12/month.
Quick comparison
| Alternative | Best for | License | Self-host | Hosted cloud? |
|---|---|---|---|---|
|
LanguageTool Open source grammar, spelling, and style checker. |
Grammar and style checking that can run fully offline on your server. | LGPL-2.1 | ★★☆☆☆ | Yes |
1. LanguageTool — Grammar and style checking that can run fully offline on your server.
Open source grammar, spelling, and style checker.
Strengths
- Supports 25+ languages.
- Self-hostable — your text never leaves your server.
- Browser extensions and editor integrations.
Weaknesses
- Grammar feel less polished than Grammarly on edge cases.
- Premium rules require paid tier or self-host config.
- Java-based deployment footprint.
LanguageTool homepage · Source on GitHub · Grammarly vs LanguageTool →
Not what you're looking for?
Browse other tools in Writing & Grammar Tools, or check out open source projects by category on the full category index.
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