A free Grammarly alternative for Mac.
Select text in any app and press ⌃⌥Space. Plume rewrites it four ways, side by side, with changes highlighted. The app is free, and you pick the model.
Plume and Grammarly, side by side.
| Criterion | Plume | Grammarly |
|---|---|---|
| How it works | Select text, press ⌃⌥Space, get four rewrites | Underlines suggestions as you type |
| Versions | Four full rewrites side by side: Proofread, Clearer, More polished, Shorter | Suggestion cards for spelling, grammar and clarity. Full-sentence rewrites on Pro |
| Your own styles | Edit the four versions and their prompts, or add your own | Tone adjustment on Pro |
| Model | A free model, or GPT, Claude or Gemini | Chosen by Grammarly |
| Price | Free app. A free model, or pay OpenRouter for GPT, Claude or Gemini | Free plan with 100 AI prompts a month. Pro is $12 a month billed yearly, about $30 billed monthly |
| Account | No Plume account. A free OpenRouter key | Grammarly account |
Grammarly facts as of October 2026: plans, Mac user guide.
What Plume does differently.
Grammarly underlines mistakes as you type. Plume works when you ask: select a paragraph, press ⌃⌥Space, and compare four full rewrites, with changed words highlighted. Return replaces your text, and ⌘Z undoes it.
You decide what the versions do. Edit their prompts or add your own in Settings, or type “shorter” or “keep it casual” to redo all four. You also pick the model: a free one, or GPT, Claude or Gemini with OpenRouter credit.
Frequently asked questions
Does Plume check my writing as I type?
No. Plume reads text only when you select it and press ⌃⌥Space. Nothing runs while you type.
Is Plume free?
Yes. With a free OpenRouter key, Plume uses a free model. Add credit to OpenRouter to pick GPT, Claude or Gemini. You pay OpenRouter directly.
Can I make my own versions?
Yes. In Settings, edit the prompt of each version or add your own.
Where does my text go?
Only to OpenRouter, when you press ⌃⌥Space. Plume has no account or server, and it skips password fields.