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CMD-C.app vs Grammarly

Two fact sheets from our own research, side by side — pricing, platforms, API access and status re-checked by us rather than quoted from the vendors. CMD-C.app starts at $2.99, Grammarly at $12. Both have a free tier.

CMD-C.appTriple-tap Cmd-C on macOS to run AI grammar and style correction on selected text in any app.GrammarlyGrammar, tone and rewriting help inside every app

Side by side

FactCMD-C.appGrammarly
CategoryGrammar & ProofreadingGrammar & Proofreading
Pricing modelFreemiumFreemium
Starts at$2.99 month$12 month
Public APINoNo
PlatformsmacOSWeb, Chrome Ext, Windows, macOS, iOS, Android
CompanyCMD-CSuperhuman
Launched—2009
Last verifiedSep 1, 2026Sep 6, 2026

What our research says

CMD-C.app

CMD-C's system-wide shortcut avoids the usual grammar-checker friction of copying text into a separate app, and the bring-your-own-API-key option makes it effectively free for anyone who already pays for OpenAI or Claude directly. It's macOS-only and, being a small utility, comes with no visible company behind it to vouch for long-term support.

Pros

  • Works inside any macOS app via a keyboard shortcut, no copy-paste to a separate tool
  • Free tier available for users with their own API key
  • Cheap paid tier at under $3 a month for 8,000 corrections
  • Correction history with explanations, not just silent edits

Cons

  • macOS only, no Windows or Linux version
  • No identifiable company or team behind the product
  • Free tier depends on the user already holding a separate paid API key

Grammarly

Still the default for catching mistakes inside other people's software, but the free tier has quietly become an AI-prompt meter and the honest price is $30 unless you commit to a full year.

Pros

  • Runs inside the apps people already write in rather than as a separate editor
  • Free tier still covers spelling, grammar and tone detection with no time limit
  • Pro folds in plagiarism and AI-text detection that rivals charge for separately

Cons

  • The $12 headline is the annual rate; paying monthly costs $30
  • Free AI allowance is 100 prompts a month and depletes quickly
  • No public API, so it cannot be embedded in another product
  • Enterprise pricing is not published anywhere on the site

Which one fits

Choose CMD-C.app if you need

  • macOS users who want grammar correction without leaving their current app
  • People who already have an OpenAI or Claude API key and want a free option
  • Anyone wanting an editable prompt and a correction history

Choose Grammarly if you need

  • Anyone writing in a browser, Word or email who wants corrections in place
  • Teams enforcing a house style guide across people who are not writers
  • Non-native English speakers who want fluency rewrites, not just error flags

More comparisons

Browse all Grammar & Proofreading →