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LanguageTool
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LanguageTool

German AI grammar and style checker for 30+ languages — better than Grammarly in German

Website
Pricing:Freemium
From:5.83 €/Mo
Free Trial:Yes ✓
85/ 100Gesamtwertung
Benutzerfreundlichkeit
9.0
Funktionsumfang
8.0
Preis-Leistung
9.0
KI-Qualität
8.0
★4.6 auf G2 · 982 Bewertungen↗

Our LanguageTool review 2026 tests the German AI writing assistant with grammar, style, and tone checking for 30+ languages. Premium from €5.83/month (annually).

Pros & Cons

Vorteile

  • Best grammar and style checking in German — significantly outperforms Grammarly for German texts.
  • Supports 30+ languages with linguistically deep rule sets.
  • Broad platform integration: Google Docs, Word, Gmail, browser extensions, desktop apps.
  • Open-source version available for self-hosted enterprise installations.
  • More affordable than Grammarly Premium — €5.83/month annually for full features.

Nachteile

  • Less mature AI writing than dedicated tools — no text generation feature.
  • Grammarly is still stronger for English text style and tone analysis.
  • Team management features less mature than enterprise solutions.
  • Offline use only with self-hosted server or desktop app with limited features.
  • No integration with Notion or Figma — only standard office tools.

Features

Deep German Language Checking

LanguageTool is particularly strong in German and detects complex grammar errors, comma placement by German rules, case agreement, and stylistic weaknesses.

Over 30 Languages

LanguageTool supports over 30 languages including German, English, French, Spanish, Polish, and more — ideal for multilingual teams and international communication.

Style Suggestions and Clarity Analysis

Beyond grammar, LanguageTool also analyzes style: it detects word repetitions, unnecessary filler words, passive-heavy sentences, and suggests clearer phrasings.

Open-Source Core

LanguageTool has an open-source core (available on GitHub), maintained by an active community — companies can also self-host the software.

Browser Extension for All Web Interfaces

As a browser extension for Chrome, Firefox, and other browsers, LanguageTool checks text in Google Docs, Outlook, Gmail, WordPress, Notion, and any other web interface.

API for Developers

The LanguageTool API enables integration of grammar checking into custom applications, editors, or content management systems — with usage-based billing.

In Detail

A thorough LanguageTool review in 2026 confirms that this Berlin-based company offers the superior grammar and style checking tool for German-speaking users. While Grammarly was primarily developed for English, LanguageTool is optimized for over 30 languages — with particular strength in German, French, and Spanish.

Superior German Language Competence

LanguageTool was developed by linguists and features deep rule sets for German grammar — including complex case usage, gender distinctions, and comma placement that many other tools get wrong. The AI-powered style checker detects not just grammar errors but also provides improvement suggestions for clarity, conciseness, and readability.

Broad Platform Integration

LanguageTool integrates seamlessly into most writing environments: Google Docs, Microsoft Word, Gmail, Outlook, and via browser extensions into any web form. Desktop apps for Windows and Mac enable system-wide spell checking across all applications.

Privacy and Open Source

LanguageTool offers an open-source version for self-hosted instances — ideal for companies with strict data privacy requirements. The standard cloud version is GDPR-compliant and does not permanently store texts.

FAQ

LanguageTool is significantly stronger for non-English languages, especially German, and has an open-source core. Grammarly is better at English style and has more AI writing features (GrammarlyGO). For German texts, LanguageTool is the better choice; for English, Grammarly often wins.

The basic version is free with fundamental corrections. Premium costs around €4.99/month (annual subscription) and offers extended style suggestions, synonyms, readability analysis, and more rules. Team plans for businesses are also available.

Yes, the open-source core of LanguageTool can be hosted on your own servers — ideal for businesses with privacy requirements that don't want to send text to external servers. Documentation is available on GitHub.

LanguageTool is excellent for checking grammar, spelling, and basic style. For high-quality content work (tone, persuasiveness, SEO), supplementary tools are needed. As a proofreading tool, however, it is very precise — especially for German.

The cloud version requires an internet connection. For offline use, LanguageTool is available as a desktop application and as a self-hosted option. The browser extension sends text to LanguageTool servers for analysis.

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