LanguageTool - Grammar & Style Checker - Supports 25+ Languages, Plugins for Chrome, Firefox & GDocs
Check your texts for spelling, grammar and style issues everywhere on the web.
* Supports 25+ languages (English, German, Spanish, French, Dutch, Portuguese, ...)
* Open source (can be self-hosted)
* Plugins for Firefox, Chrome and Docs
LanguageTool - Open source Grammarly alternative
LanguageTool checks your writing in more than 20 languages