LanguageTool
← Back to All AI Tools1. Should you try LanguageTool? Overview
| What it is | Multilingual grammar, style and paraphrasing checker available as a web editor, browser/office add-ins and self-hostable open-source engine, covering 30+ languages. |
| Country / HQ | Potsdam, Germany (LanguageTooler GmbH, founded 2003; acquired by US Learneo in 2023) |
| Best for | Writers and teams working across multiple languages who want privacy-friendly, self-hostable grammar checking beyond English. |
| Check before buying | Free tier limits check size (~10K characters) and advanced suggestions. Some AI features need Premium. US ownership since 2023. |
| Editor rating | ~4.5/5 (editor, widely used) |
| Pricing signal | Free tier + paid |
2. Features What it does
| Feature | What it does |
|---|---|
| 30+ languages | Grammar and style checks across English, German, Spanish, French and more. |
| AI paraphrasing | Premium rewrites and tone adjustments. |
| Open-source engine | LGPL-licensed core can be self-hosted for privacy/data control. |
| Add-ins | Word, Google Docs, browser and desktop integrations. |
| API | Programmatic checking for apps and workflows. |
3. Pricing Pricing (2026-10, USD)
| Plan | Price / mo | Key limits & who it fits |
|---|---|---|
| Free | $0 | Basic checks, ~10K characters per check. |
| Premium Individual | ~EUR19.9/mo | Unlimited length, advanced style, AI features (cheaper annually ~$5-8/mo). |
| Teams | Per seat | Central billing and team management. |
4. Integration Access & integrations
| Access type | Details |
|---|---|
| Access | Web, desktop, browser extension, Office/Google Docs add-ins, API. |
| Privacy | Self-host option; EU origins (now US-owned Learneo). |
5. Reviews & Sources External reviews
| Source | Rating | What it says |
|---|---|---|
| Editor | ~4.5/5 | Best multilingual grammar checker and rare self-hostable option; free tier is limited in length. |
| Users | — | Praised for language breadth and privacy; Premium AI features lag some rivals. |
| Source | — | languagetool.org; 2026 writing-tool roundups. |
6. Best for / Not for Fit
| ✔ Suitable | ✘ Not suitable |
|---|---|
| • Multilingual writers and editors • Privacy-conscious teams wanting self-hosting • Developers needing a grammar API |
• Users wanting a fully free unlimited checker • Those needing deep generative rewriting (Premium only) • Shops standardized on a single English tool |
7. Competitors How it compares
| Competitor | How it differs | Best for |
|---|---|---|
| Grammarly | Stronger English AI, less multilingual | English writers |
| ProWritingAid | Deep English style reports | Authors |
| QuillBot | Paraphrase-first, limited languages | Students |
8. Summary Verdict
| Takeaway | LanguageTool is the leading multilingual and self-hostable grammar checker – a privacy-friendly alternative to English-centric tools, with a free tier that is length-limited. |
| Who should pick it | Non-English or multilingual users and privacy-focused teams. |
| Who should skip it | Users wanting unlimited free checks or English-only generative depth. |