LanguageTool is a multilingual grammar, spelling, and style checker with an open-source core. Long established and German in origin, it is now part of Learneo, the same education group behind QuillBot and Scribbr. Its stand-out qualities are threefold: it checks more than 30 languages at a genuinely high level, it puts privacy first with a self-hostable engine, and its Premium plan costs far less than Grammarly. It suits students, non-native writers, multilingual professionals, and privacy-sensitive teams. The main takeaway from this review: for anyone writing in more than one language or who cares about data privacy, LanguageTool is the best-value grammar checker in 2026, though it lacks Grammarly’s depth in English tone and has no real plagiarism tool.
What LanguageTool Really Is
LanguageTool is a proofreading engine that catches grammar, spelling, punctuation, and style problems as you write. What sets it apart is its foundation: a huge set of language-specific rules built and maintained by professional linguists and an open-source community, not just an English tool with other languages bolted on. It supports more than 30 languages at native quality, distinguishes British and US English, and adds AI-powered phrasing suggestions on top. It reviews your writing; it does not generate content from scratch.
Putting It To Work Day To Day
Using it is refreshingly low-friction. You can paste text straight into the editor at languagetool.org with no account, or install the browser extension so it checks your writing inside Gmail, Google Docs, WordPress, LinkedIn, and almost any text field. Errors appear underlined, with a sidebar explaining each fix so you learn as you go. You can build a personal dictionary, switch between language variants, and, on Premium, turn on picky mode for stricter, more polished suggestions.
Everything Packed Into The Suite
- Multilingual checking: Grammar, spelling, and style across 30+ languages.
- Style and picky mode: Advanced suggestions for cleaner, sharper writing.
- Open-source core: LGPL engine you can inspect and self-host.
- Broad integrations: Browsers, Word, Google Docs, desktop apps, and email.
- Personal dictionary: Add your own words and terms to avoid false flags.
- Public API: A REST API for hosted or self-hosted custom use.
How It Holds Up In Real Writing
For everyday grammar and spelling, LanguageTool is dependable and fast, and its multilingual accuracy is genuinely strong, especially in German, French, and Spanish, where it often beats English-first rivals. The free tier alone catches most common mistakes. The honest limits: its English tone and style suggestions are lighter than Grammarly’s, and the always-on highlighting can feel distracting during heavy drafting. It also lacks a serious plagiarism checker, so it is a proofreader, not a full writing suite.
How It Slots In With Your Stack
LanguageTool runs almost everywhere: Chrome, Firefox, and Edge extensions, a Word add-in, Google Docs, desktop apps for macOS and Windows, mobile, and a REST API. Its open-source, self-hostable engine is the real differentiator, letting privacy-sensitive organizations keep text entirely on their own servers. It shares a parent company with QuillBot and Scribbr under Learneo. It is not a content generator like  ChatGPT, and not a tone-and-style powerhouse like Grammarly. It is a multilingual proofreader with a privacy edge.
Where it comes up short
Is LanguageTool Safe And Private?
This is where LanguageTool genuinely leads. The core engine is open source under the LGPL license, so anyone can inspect how it works. By default it stores no text, and organizations can self-host the whole engine, meaning sensitive writing never leaves their own servers. For legal firms, healthcare providers, and government teams with strict data rules, that self-hosting option is a decisive advantage that cloud-only tools like Grammarly cannot match. For everyday users, the privacy-first design is simply reassuring.
This is the live LanguageTool pricing, and it corrects what my sources had. Important: every price on this screenshot is a 50% promo price, not the regular price. The struck-through numbers are the real (non-discounted) prices. I’ll show both so your page stays honest when the promo ends.
Here’s the separate pricing table built straight from the screenshot:
LanguageTool Pricing Individual (Premium)
| Billing period | Promo price (–50%) | Regular price | Billed as |
|---|---|---|---|
| 2 years | $2.50/mo | $5.00/mo | $59.90 / 2 years (was $119.80) |
| Annual | $2.91/mo | $5.82/mo | $34.95/year (was $69.90) |
| Quarterly | $8.32/mo | $16.64/mo | $24.95/quarter (was $49.90) |
| Monthly | $12.45/mo | $24.90/mo | $24.90/month |
LanguageTool Pricing Teams
| Plan | Promo price (–53%) | Regular price | Billed as |
|---|---|---|---|
| Teams (2 users) | $5.53/mo | ~$11.65/mo | $66.40/year (was $139.80), i.e. $33.20/user/year |
Free plan (not on this screenshot but confirmed): $0 grammar, spelling, basic style, per-check character limit, no sign-up.
Three honest points before you publish this:
- These are discount prices. Don’t publish them as the standard price. The $2.91/mo annual is with 50% off. Regular annual is $5.82/mo ($69.90/year). If you write “$2.91/mo” flat, your page is wrong the moment the promo changes, and readers who click through and see a different number lose trust in your site. My table shows both columns so you’re covered either way.
- My earlier page said “~$4.99/mo.” That was from third-party sources and is now corrected by your screenshot the real regular annual rate is $5.82/mo, promo is $2.91/mo. Update the page’s pricing section AND the schema
offersblock (currently ~$4.99) to match this. A wrong price in schema shows a wrong price in Google’s rich result. - The “150,000 characters per text field” detail is worth adding that’s the Premium limit, and your keyword data has people asking about limits. It’s a concrete spec that helps both readers and AI Overviews.
| Best for | Main use | Pricing model | Platforms | Key limitation |
|---|---|---|---|---|
| Multilingual & privacy-conscious writers | Grammar, spelling, and style checking | Freemium (verify at languagetool.org) | Web, browsers, Word, Docs, desktop, API | Lighter English tone tools; no strong plagiarism check |
The Imperial AI Tools Verdict
LanguageTool wins on the things that matter to a specific, large group of writers: languages, privacy, and price. Its multilingual accuracy is excellent, the open-source self-hosting option is unmatched among mainstream grammar tools, and Premium at around $4.99 a month undercuts Grammarly by roughly half. The free plan is one of the best in the category and needs no sign-up. The trade-offs are clear and worth stating. Its English tone and style suggestions are lighter than Grammarly’s, the constant highlighting can distract during drafting, and there is no serious plagiarism checker. Our overall view: if you write in multiple languages or care about data privacy, this is the smartest-value grammar checker in 2026. If you write only in English and want maximum polish, Grammarly still edges it.
What Could Make It Better
- Deepen English tone and style suggestions.
- Add a stronger built-in plagiarism checker.
- Offer a calmer, less distracting highlighting mode.
- Expand live support options for paid users.
- Make the self-hosting setup easier for non-technical teams.
- Keep pricing clear across billing periods and regions.
