LanguageTool, your multilingual writing assistant

Think auto-correct and grammar-checking tools are old hat? Think again!

With the advent of artificial intelligence, language tools have gone far beyond checking spelling or catching missing punctuation. Today’s tools consider context and advise you on the tone of your copy, helping you write more clearly and effectively. They will even double-check things like international bank account numbers or alert you when you write “Monday, January 13, 2021” — because that’s actually a Wednesday!

One very popular tool for this is Grammarly. But there’s one big caveat: It only speaks English. If you’re a Grammarly user who wished it could also help you with, say, Spanish or German, you may have been excited to learn about Microsoft’s “Editor.” It supports 20 languages and works in all Office apps and major web browsers (except Safari), but to get the good stuff, you need a Microsoft 365 subscription. So today, we’d like to tell you about another option: LanguageTool.

LanguageTool goes beyond grammar, offering AI-driven writing suggestions in over 30 languages.

LanguageTool currently supports 30+ languages and language variants to different degrees. The depth of spelling, grammar, style, and Premium checking varies by language, so it is better to think in terms of coverage rather than a simple “supported / unsupported” list.

Its most extensive Premium checks currently cover English, German, French, Spanish, Dutch, Polish, and Portuguese. Other supported languages include Arabic, Catalan, Danish, Greek, Italian, Romanian, Russian, Swedish, Ukrainian, Chinese, Japanese, and many more. Before adopting it for a specific language pair, check the current language-support list to see which features are available.

LanguageTool still has an open-source core, so developers and language enthusiasts can inspect and contribute to parts of the project. However, the hosted service now includes commercial Premium, account, team, and AI features that go beyond the open-source core.

LanguageTool can be used almost anywhere people get writing done: Microsoft Word, Google Docs, LibreOffice, Apple Pages, and major browsers such as Chrome, Edge, Firefox, Safari, and Opera. It also works in email environments including Gmail, Apple Mail, Thunderbird, and Outlook beta, and offers desktop apps for macOS and Windows.

LanguageTool offers spelling, grammar, style, and rewriting help across email, browsers, and word processors.

Once installed in your browser, LanguageTool is always close at hand. It can help you write more effective emails, catch embarrassing typos on social media, and polish text in many web-based tools. If you do not want assistance on a particular site, you can disable LanguageTool there.

The current product also goes beyond traditional checking. Its AI-powered paraphrasing can rewrite sentences to make them more formal, fluent, concise, or stylistically appropriate. The free tier includes a limited number of AI paraphrases per day, while Premium offers more extensive checking and unlimited AI-powered sentence paraphrasing.

If you create an online account, you can save preferences and documents, build a personal dictionary, and use additional customization features. Picky mode still provides stricter checks for issues such as wordiness and style. Newer tools such as Writing Goals and Style Guides can also help tailor suggestions to the type of text you are writing or enforce preferred terminology and wording — particularly useful for editors, translators, and teams working to a house style.

Any time you are working online, privacy is paramount. LanguageTool processes text on its servers for many online features, but the old blanket statement that “what you write isn’t stored” is no longer accurate for every workflow. Browser and app checks are generally processed without permanently storing the full submitted text, although some temporary processing and usage data may be retained. If you save a document in the LanguageTool Editor, that content is stored so you can access it again.

For language professionals handling confidential client material, the safest approach is to review the current LanguageTool privacy policy and your client, NDA, and organizational requirements before using any cloud-based writing assistant. LanguageTool is now part of Learneo, Inc., which is identified as the data controller in the current privacy policy.

So what does it cost? LanguageTool still uses a freemium model. Basic use is free and includes core grammar, punctuation, and style checking, plus a small number of AI-powered paraphrases. Premium adds substantially more advanced checks in its strongest languages, higher text limits, unlimited AI sentence paraphrasing, and features such as Style Guides. Because prices vary by region, billing period, tax, and promotions, check the current pricing page rather than relying on a fixed monthly figure.

The bottom line? LanguageTool is no longer simply “the multilingual alternative to Grammarly.” Grammarly itself is now multilingual. LanguageTool’s appeal today is its unusually broad language coverage, flexible integrations, open-source roots, and combination of classic grammar checking with newer AI-powered rewriting and professional style controls.

First published in December 2020. Revised in August 2026.