This is language tools use for writing correct grammar.  It is having browser extensions and plugin so that you can use for word editor like google docs, Microsoft words etc.

Try the Language Tool Editor

1. For a Better Writing Experience.
2. Distraction-free writing experience
3. Personal Dictionary 
4. Quality scoring for evaluating style and grammar Texts are securely stored Access even more
5. suggestions for advanced punctuation, style, and typography with the “Picky Mode”
   Choose between dark and light appearance

Price : Free, Premium

Site Link : LanguageTool