Overview
LanguageTool is a multilingual writing assistant for grammar, spelling, punctuation, style, and tone checking. Its official site provides a browser editor, paraphrasing, browser add-ons, email integrations, office plugins, and desktop applications. The core engine is open source and is available under the LGPL-2.1-or-later license. The official GitHub repository also documents a command-line application, a Java API, an HTTP API, and ways to run a private server. The hosted service adds premium features and business-oriented options, so the open-source repository does not represent every commercial feature.