LanguageTool
AI-powered grammar, style, and spell checker for 30+ languages
About LanguageTool
LanguageTool is an open-source-based writing assistant that checks grammar, spelling, punctuation, and style in over 30 languages. Available as browser extensions, desktop apps, and integrations with Google Docs and Microsoft Word, it offers AI-powered paraphrasing and more than 20,000 additional writing rules for premium users.
Pros & Cons
Pros
- Supports 30+ languages — broadest multilingual grammar checking on the market
- Open-source core offers transparency and self-hosting option for privacy-conscious users
- Very affordable at half the price of Grammarly for comparable features
- Excellent browser and office integrations for seamless real-time checking
- AI-powered paraphrasing helps improve writing style beyond just fixing errors
- Custom rules feature useful for enforcing brand voice and terminology
Cons
- Free version has limited character count and fewer rules
- No built-in plagiarism checker unlike some competitors
- Lacks advanced generative AI writing features like Grammarly's
- Some suggestions can be inaccurate or miss context-specific errors
- Onboarding experience could be more intuitive for new users
Key Features
Multilingual Support
Checks grammar, spelling, and style in over 30 languages including English, German, French, Spanish, Dutch, and Polish
AI-Powered Paraphrasing
Rephrase sentences to be more formal, fluid, or concise using AI suggestions
Browser Extensions
Available for Chrome, Edge, Firefox, Safari, and Opera for real-time checking across all websites
Office Integrations
Works with Microsoft Word, Google Docs, LibreOffice, and email clients
Desktop Apps
Native applications for Windows and macOS with system-wide checking
Style & Tone Suggestions
Goes beyond grammar to improve writing style, clarity, and professional tone
Custom Rules
Create custom rules to enforce consistent wording and terminology across your writing
Personal Dictionary
Add custom words and terminology to prevent false positives
Pricing
- 10,000 characters per check
- Basic grammar and spelling
- 30+ languages
- Browser extension
- 100,000 characters per check
- 20,000+ additional rules
- AI paraphrasing
- Style suggestions
- Custom rules
- All integrations
- Everything in Premium
- Team management dashboard
- Centralized billing
- Priority support
- 2+ users required
Best For
Multilingual Business Communication
Check emails, reports, and documents in multiple languages for international teams and businesses
Academic and Research Writing
Polish academic papers, dissertations, and research articles with advanced grammar and style suggestions
Content Creation & Blogging
Ensure blog posts, articles, and marketing copy are error-free and professionally written
Non-Native Language Writing
Get extra support writing in a second language with language-specific grammar rules and suggestions
Team Writing Standards
Use custom rules and team features to maintain consistent writing quality across an organization
Similar Tools
QuillBot
AI-powered writing and paraphrasing suite
Grammarly
AI-powered writing assistant for clear, effective communication
Smartly.AI
Generative AI Powered Chatbots for Customer Service
Cohere
Your next breakthrough, powered by AI
Contenda
Repurpose technical content into blogs, tutorials, and more — automatically
D-ID
AI-Powered Video Creation with Talking Avatars
Featured In
Best Grammar Checkers for ESL Writers (2026)
Best for multilingual ESL writers and academics who want privacy-friendly, rigorous grammar checking.
Best Grammar Checkers for Non-Native English Writers (2026)
Best for multilingual writers, academics, and anyone who needs solid grammar checking without enterprise-tier pricing.
Grammarly Alternatives That Work in More Apps (2026)
Best for power users, multilingual writers, and anyone whose biggest gripe with Grammarly is 'it only works in the browser' — LanguageTool's native desktop app is the closest thing to a true system-wide replacement.