Compare software

RefineHarper
Free

Free to download and use without an account.

 Free

Free and open source.

macOS macOS, Web, Browser extension, Command line
  • Grammar checking runs locally and works offline
  • Every fix explains the rule behind it
  • All checks run locally with no telemetry
  • Works in browsers, editors and system-wide on macOS
  • macOS only, requires macOS 14 or later
  • Local model quality depends on the Mac it runs on
  • English only
  • Rule-based checks do not rewrite text the way AI assistants do
Downloadable app Downloadable app, Web application, Browser extension
Closed source Open source
License not stated License not stated
No account needed Not stated if an account is needed
Works offline Works offline

Checked October 1, 2026

Checked September 26, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.