What LanguageTool actually does
LanguageTool is a grammar and style checker built by LanguageTooler GmbH, a company headquartered in Hamburg, Germany. Unlike many English-only checkers, it supports more than 20 languages, and it's available almost everywhere you write: browser extensions, a web editor, Office and Google Docs plugins, and desktop apps for Windows and macOS.
The core product
At its core, LanguageTool scans text for spelling mistakes, grammar errors and basic punctuation and casing issues, underlining problems and suggesting fixes as you type — the same category of tool as other grammar checkers, but built to work across dozens of languages rather than treating English as the only real use case. It's commonly used by people writing or proofreading in a second language, since it can catch mistakes that come from translating sentence structure too literally from another language, not just typos.
The free plan checks text in chunks of up to 2,000 characters, includes a personal dictionary and basic text statistics, and gives access to the same browser extensions, desktop apps and document plugins as the paid tier — the difference on the free plan is depth and volume, not which apps you're allowed to use.
What's new or notable
The Premium plan is where LanguageTool becomes a genuinely deeper writing tool rather than a basic spellchecker. It removes the 2,000-character check limit, raising it to up to 150,000 characters per text field, which is enough to check a long document in one pass instead of copying it in sections.
It also adds:
- More than 20,000 additional style and clarity checks on top of the free plan's basic grammar rules
- Unlimited AI-powered sentence paraphrasing (versus a handful of free paraphrases a day)
- A personalizable Style Guide for enforcing your own writing rules consistently
Above individual Premium, a separate Team plan scales for organizations of 2 to 1,000+ users, adding shared team dictionaries, a shared team style guide, and centralized user management via email invitations, so a whole company can enforce consistent terminology and tone.
Who should use LanguageTool
Great fit if…
- You write in more than one language. Support for 20+ languages, rather than English only, is the main reason to pick LanguageTool over many competitors.
- You want grammar checking inside the apps you already use. Browser extensions, Google Docs, Microsoft Word, LibreOffice and desktop apps are all covered, including on the free plan.
- You write occasional shorter documents. The free plan's 2,000-character check limit and daily paraphrase allowance are enough for emails, social posts and short drafts.
- You're a second-language writer who wants to catch translated-sounding phrasing. LanguageTool is specifically useful for catching the kind of error that comes from thinking in one language and writing in another.
Skip it if…
- You regularly check long documents in one sitting. The free plan's 2,000-character limit means splitting long text into pieces; Premium's 150,000-character limit removes that friction, but it costs extra.
- You rely heavily on AI paraphrasing. Free-tier paraphrasing is capped at just a few uses a day, so anyone who wants to rephrase sentences often will hit the wall quickly.
- You need advanced style and clarity feedback, not just basic grammar. The 20,000+ additional checks that catch subtler style issues are Premium-only; the free plan's feedback is comparatively basic.
Pricing in detail
LanguageTool's free plan covers the basics; Premium adds depth and volume, and pricing drops substantially with an annual commitment.
| Plan | Price | What's included |
|---|---|---|
| Free | €0 | Grammar, spelling, punctuation and casing checks up to 2,000 characters per check, access to 20+ languages, personal dictionary, text statistics, and up to 3 AI paraphrases a day, across browser extensions, desktop apps and document plugins. |
| Premium | €19.90/month billed monthly, or roughly €4.90/month on the annual plan | Checks up to 150,000 characters per text field, more than 20,000 additional style and clarity checks, unlimited AI sentence paraphrasing, a personal Style Guide, and all free-plan features. |
| Team | Scales with team size (2–1,000+ users); exact per-user rate not published | All Premium features for each member, plus shared Team Dictionary and Team Style Guide, and centralized user management via email invitations. |
Where it falls short
- Free checks are capped at 2,000 characters per pass. Long-form writing — a full report, a long email thread, an essay — has to be checked in pieces rather than all at once unless you upgrade.
- Free paraphrasing is limited to only a handful of uses per day. Anyone who leans on AI rewriting as part of their normal editing process will run out quickly and need Premium for unlimited use.
- The deepest style and clarity feedback is Premium-only. The more than 20,000 additional checks that catch tone, clarity and style issues beyond basic grammar sit entirely behind the paid tier.
- Team pricing isn't published up front. Organizations have to go further into the sign-up or sales process to see per-user Team costs, rather than comparing them directly against Premium on the pricing page.
Privacy & data
As a Hamburg-based company, LanguageTool operates under GDPR, which gives EU users baseline rights over how their text is processed and stored regardless of plan. LanguageTool's core function requires sending the text you write to its servers to be checked, which is inherent to how any cloud-based grammar checker works — the practical privacy question for a given user is less about jurisdiction and more about how long that text is retained and whether it's used to improve LanguageTool's models.
We were not able to confirm specific retention or model-training details for free versus Premium use from the public pricing and feature pages checked for this review, so anyone checking sensitive or confidential documents regularly should review LanguageTool's current privacy policy directly before relying on it for that kind of text.
How we checked this
This review is based on LanguageTool's public pricing page (languagetool.org/pricing), checked on 4 September 2026, describing the Free, Premium and Team plans and their respective feature sets. Some figures, including the precise wording of "more than 20,000 additional checks," are LanguageTool's own marketing language rather than an independently verified count. We did not conduct hands-on testing of grammar-detection accuracy across languages for this write-up.