Korr

The French and English grammar checker
that never sees your text

Everything runs in your browser. No server, no account and no limits. It even works without an internet connection.

Grammar checker

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Two languages, two specialized engines

Complex French agreements

Past participles, pronominal verbs and long-distance agreements.

les décisions qu'il a pris → les décisions qu'il a prises

French tenses and subjunctive

Conditional clauses and the subjunctive after expressions such as « bien que ».

si j'aurais su → si j'avais su

French homophones

et/est, ou/où, sa/ça and quand/quant, resolved using context.

elle et partie → elle est partie

French text-message language

Nearly 180 abbreviations are recognized and expanded into proper French.

slt jsui dsl → Salut je suis désolé

French typography

Correct spacing before ! ? : ; without changing URLs or times.

exceptionnel! → exceptionnel !

English grammar

Compound tenses, common confusions, missing words and incorrect expressions.

I have went home → I have gone home

Natural English

Harper catches phrases such as could of and incorrectly joined words.

could of, alot → could have, a lot

French-speaker false friends

The word-for-word translations only a French speaker writes, caught and turned into idiomatic English.

assist to the meeting → attend the meeting

Prepositions and uncountables

The preposition each verb takes, and the English nouns that never go plural.

it depends of → it depends on

Why “offline” is more than a promise

The open-source Grammalecte and Harper engines run on your device. This page never sends text to an analysis server because no such server exists.

The source code is public under the GPL 3.0 license, so this claim is verifiable. After the first correction in a selected language, its engine remains available offline.

Correct text anywhere on your PC

Install the Windows app, select text in any program - Word, Outlook, Discord or a game - press Ctrl+Alt+C, and Korr replaces it with the correction.

⬇ Download Korr for Windows Installer · about 31 MB
  • Download Korr-Setup.exe
  • Double-click the installer
  • Follow the short setup wizard
  • Launch Korr from the Start menu
  • Select text, then press Ctrl+Alt+C

Korr is not digitally signed yet. If Edge blocks the download, open downloads with Ctrl+J, then choose Keep and Keep anyway. If Windows SmartScreen appears, select More info, then Run anyway.

Other ways to use Korr

Web app

Install this page as an app. It opens offline on desktop and mobile devices.

From your browser menu, select “Install app”.

Browser extension

Correct text directly in Gmail, Slack or any text field without copying and pasting.

Coming soon to Edge Add-ons and the Chrome Web Store.