Nogrammerly

Nogrammerly is a menu bar writing assistant that checks text in most apps. It underlines spelling, grammar, wordiness and hedging problems in the field you are typing in. A right-click offers replacements or adds a word to the dictionary, and a floating button in the field rewrites the selection or the whole text in a professional, friendly, confident or concise tone. Spelling uses the system checker and built-in rules, while suggestions and rewrites run on Apple's on-device model. It suits people who want writing help without sending their text to a cloud service.

It requires macOS 14 or later on Apple silicon. The AI checks and rewrites need macOS 26 or later with Apple Intelligence turned on; without it you still get spelling and style checks. The DMG is not notarized, so the first launch is blocked until you choose Open Anyway under System Settings → Privacy & Security. The app needs Accessibility access to read the text field and draw underlines. Other checkers such as Grammarly can overlap with its underlines and should be switched off.