[emarsden]

There is a big difference in terms of privacy: LanguageTool is open source and you can run it on your own computer. You can install it as browwer plugin, a LibreOffice plugin, or a standalone server that you can access from Emacs for example (the latter is no longer promoted on their website, but you can download JAR files from https://languagetool.org/download/).

[k__]

Yes, but from what I got, only the basic features are open source and self-hostable. The premium features that bring it on-par to Grammarly aren't part of that.