Does GrammarFast work in any app?
If you can select text on macOS, GrammarFast can usually fix it. That includes Slack, email, Notes, and the other places you type all day.
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GrammarFast
Stop secound-guessing you're writing.
Fixes the grammar, keeps the personality.
50% off — early adopters only
€9.90
€4.95
/ month
Early adopter rate · Locked in for life · Cancel any time
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Questions, answered
Does GrammarFast store my text?
No. Your selected text is processed in-flight, sent back, and not stored, logged, or used for training.
Do I need to pay before downloading?
No. Get the app onto your Mac first. Payment can wait until later in the setup flow.
Is there a length limit?
GrammarFast is built for chat-length messages, so selections are capped at around 1,500 characters. Enough for a long Slack message, but not for full documents.
Is there a daily usage cap?
There's a soft cap in place to keep spam and abuse off the service. Normal daily use, even a chatty day, won't come close to hitting it.
Something not working?
Email hello@grammarfast.app. I read every message.