The best open source alternative to LanguageTool is Harper. If that doesn't suit you, our users have ranked more than 100 alternatives to LanguageTool and 17 is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to LanguageTool are Grammalecte, Eloquent Proofreading Assistant, Vale and proselint.
Harper is an English grammar checker designed to be just right. I created it after years of dealing with the shortcomings of the competition.
Eloquent is a proofreading software for English, Spanish, French, German, Portuguese, Polish, Dutch, and more than 20 other languages. It finds many errors that a simple spell checker cannot detect.
Writing is notoriously hard, even for the best writers, and it's not for lack of good advice — a tremendous amount of knowledge about the craft is strewn across usage guides, dictionaries, technical manuals, essays, pamphlets, websites, and the hearts and minds of great...
We use artificial intelligence and natural language processing technology to find your writing errors and offer smart suggestions.
RewritePal is a free, AI-powered tool designed to make your writing clear, compelling, and tailored to any audience. Whether you're a student, professional, or content creator, RewritePal helps you transform paragraphs into polished, reader-friendly text in seconds.
Grammark helps improve writing style & grammar and teaches students to self-edit. Basically, it finds things that grammarians consider bad, highlights them, and suggests improvements.
Naive linter for English prose for developers who can't write good and wanna learn to do other stuff good too.
Scramble is an open-source Chrome extension that leverages AI to enhance your writing directly in your browser. It's designed to be a more customizable and privacy-respecting alternative to Grammarly.
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