Korr is a completely free grammar checker for French and English. It asks nothing of you: no account, no subscription, no usage limits. And unlike Grammarly, your text never leaves your device, because there is no analysis server to send it to.
No signup. No download required. Open the page and start correcting. 100% free, no limits, no account.
On Windows, Korr's signature feature is a system-wide shortcut. You don't paste text into a website - you fix it wherever you already write.
| Korr | Grammarly | LanguageTool | |
|---|---|---|---|
| Price | Free | Free tier + paid | Free tier + paid |
| Account required | No | Yes | For premium |
| Usage limits | None | Limited (free) | 10,000 characters (free) |
| Works offline | Yes | No (cloud) | No (free tier) |
| Text stays on your device | Always | No | No (free tier) |
| Review each change | One by one | One by one | One by one |
| Personal dictionary | Yes, on your device | In your account | In your account |
| French | Yes | Yes | Yes |
| English | Yes | Yes | Yes |
| System-wide shortcut (desktop) | Yes (Ctrl+Alt+C) | Via app/extension | Browser + add-ons |
Comparison based on the free tiers, as of September 2026. Grammarly added multilingual suggestions in 2025, French included, on every plan. LanguageTool's free checker allows up to 10,000 characters per text.
We ran Korr over nine corpora of forty sentences, in three languages, half of them already correct. Here is what came out, and the method is published with it.
98.67 % precision · 96.91 % F1
98.23 % precision · 96.82 % F1
100 % precision · 96.76 % F1
0 out of 174
See the full method and the misses
Korr does not silently rewrite your text. Every change is listed, shown inside its sentence and labelled, and you reject the ones you disagree with, one at a time.
Your proper nouns, brand names and trade words, added in one click: Korr stops correcting them. The list stays on your device, with no account and no sync.
No account, no subscription, no per-month quota. Every feature is available to everyone, forever.
The correction engines run on your device. There is no analysis server, so your text simply cannot be sent anywhere.
Two specialised engines, not one generic model. Complex agreements, tenses, homophones, false friends and even French text-message slang.
Fix text in any program with a keyboard shortcut, instead of copying it into a website first.
Cut your connection after the first load: the correction keeps working. "Offline" is not a promise you have to trust - you can test it.
A Windows app, and an installable web app for Android, iPhone and any browser - all running the same local engine.
Yes. Korr is 100% free. There is no paid tier, no account, no subscription and no usage limit.
Yes. After the first load of a language, its engine stays available with no internet connection. Your text is never sent to any server because no analysis server exists.
Yes, though not because Grammarly lacks French: it added multilingual suggestions in 2025. The difference is the model. Korr uses an engine built specifically for French, it runs on your machine, and it asks for no account. Grammarly analyses your text on its servers and requires you to sign up.
No. You never create an account or sign in. Open the page (or the Windows app) and start correcting.
Yes. Install the web app on Android or iPhone from your browser menu; it runs the same local engine and works offline. The system-wide Ctrl+Alt+C shortcut is a Windows feature.
Yes, on the Chrome Web Store. It corrects text directly in Gmail, Slack or any text field, without copying and pasting, and it runs the same local engines: nothing is sent anywhere. It also installs in Edge, which accepts extensions from the Chrome Web Store.