A menu-bar app for the Mac
Good writing, one keystroke away.
Select text in any app and press ⌃G. Grammai rewrites it and marks every change like an editor's pencil. Press ↵ and it's back where you were typing.
Requires macOS 15 or later.
Every change, marked.
Struck words are what you wrote; underlined ones are what Grammai suggests. Don't like a change? Click it and your original wording stays. Replace and Copy use exactly what you kept.
Try it: click a marked word, or switch to Clean.
One paragraph, six ways to say it.
Presets set the job: fix only the mistakes, polish, change the tone, tighten, or translate. Press ⇥ to flip through them, or type what you want, like “shorter” or “friendlier”. You can write your own presets too.
What you wrote
hey team, just wanted to give a quick update. the new onboarding flow is basically done but theres still a few bugs we need to fix before we can ship it, hopefully by thursday.
Make it yours.
A preset is a set of plain switches: how much to change, the tone, the length, and the small rules you care about. Tweak the built-ins or make your own, and Grammai writes the instructions for you.
Weekly update
Your preset, made from the switches below.
Style
Mechanics
Advanced
Preview
The right preset for each app
Open with Casual in chat and Formal in Mail. Grammai remembers which app you're in.
Your own dictionary
Names and terms you add are kept exactly as you write them, in every preset. Code and links stay untouched.
Share them
Export your presets to a file and hand them to your team, or import theirs. Nothing is overwritten.
Your model. Your key.
Bring a key from the provider you like, or skip keys entirely with a local model or Apple Intelligence. Keys live in your Keychain. Your text goes straight to the model you pick and nowhere else.
Switch models from the panel with ⌘M, mid-sentence.
- Anthropic ClaudeThe default. Fast and careful.
- OpenAIGPT models with your own key.
- Google GeminiGemini models with your own key.
- OpenRouterHundreds of models behind one key.
- Ollama and LM StudioLocal models. Nothing leaves your Mac.
- Apple IntelligenceOn-device, on macOS 26. No key at all.
Hands stay on the keys.
Everything in the panel has a shortcut, and every shortcut is in a menu. Go on, press a few.
- ↵Replace the selection
- escBack out, one step at a time
- ⇥Next preset
- ⌘KBrowse presets
- ⌘MSwitch model
- ⌘DChanges or clean text
- ⌘CCopy instead of replacing
- ⌘EExplain the changes
Better writing, from your menu bar.
Download Grammai, select some text, and press ⌃G. It takes a minute to set up.