Change-by-change review
Every change is listed, shown inside its sentence and labelled: accent, capital, agreement, typography. Reject the ones you disagree with, one at a time.
elle et partie → elle est partie homophone
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Every change
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Corrected in place
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5languages corrected
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100%offline, on your device
0length limit
Measured on real text
Sentences drawn at random from real texts, and the score exactly as it came out.
18.1/20 on 180 sentences, 160 of them drawn at random from real French texts
- 58 of 60 correct sentences left untouched
- 20 of 20 ambiguous cases left to the author
- 74 of 100 errors corrected
19.0/20 with advanced correction (local AI, opt-in) · 89 of 100 errors correctedAn indicative figure, to be read with caution: the errors in this test resemble the ones the AI was trained on, and some sentences may appear in its training data. The main score owes nothing to the AI.
Weighting: preservation 10 points, abstention 4, correction 6. Full measurement on unseen text
18.7/20 on 180 sentences, 160 of them drawn at random from real English texts
- 60 of 60 correct sentences left untouched
- 19 of 20 ambiguous cases left to the author
- 82 of 100 errors corrected
19.6/20 with advanced correction (local AI, opt-in) · 96 of 100 errors correctedAn indicative figure, to be read with caution: the errors in this test resemble the ones the AI was trained on, and some sentences may appear in its training data. The main score owes nothing to the AI.
Weighting: preservation 10 points, abstention 4, correction 6. Full measurement on unseen text
You stay in control of your text
Personal dictionary
Add your proper nouns, brand names and trade words in one click, and Korr stops correcting them. The list stays on your device, with no account.
Kept as written: Peekrapp, N'Golo, SARL
Five languages, five 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
Phrases such as could of and incorrectly joined words are caught.
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
Spanish diacritics and openings
The accents that change the meaning, dequeismo, queismo and the opening marks Spanish requires.
Como estas? → ¿Cómo estás?
Italian accents and congiuntivo
The grave accent written for the acute, the missing h of avere, elisions and the subjunctive.
perchè non e → perché non è
Portuguese nasals and impersonals
The final tilde a keyboard drops, the impersonal haver and fazer, and the crase of fixed phrases.
houveram opcoes → houve opções
Why “offline” is more than a promise
The correction engines run on your device. This page never sends text to an analysis server because no such server exists.
You can check it yourself: after a first correction in the language you picked, cut your connection. Everything keeps working, because nothing ever needed to leave.
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.
Two versions, both free and 100% offline. Pick the one that suits you:
Light
Korr's rules, in French and English. Small download, instant corrections.
Download the light version Installer · about 45 MBInstaller blocked? Portable ZIP (about 65 MB), nothing to install
Complete, with local AI
Everything in the light version, plus a small AI that runs on your PC and catches more French and English mistakes (sound-alike words, agreement). Nothing is sent online.
Download the complete version Installer · about 240 MBInstaller blocked? Portable ZIP (about 270 MB), nothing to install
- 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
Windows blocks the installer? That’s expected, here is what to do
Why the warning? Korr is not yet signed with a publisher certificate, a service paid for every year. Windows then warns about any recent program that few people have downloaded so far: the warning does not mean the file is dangerous.
- In Edge, if the download is blocked: open the downloads list with Ctrl+J, hover over the file, click … then Keep, then Show more and Keep anyway.
- In Chrome: click Keep in the downloads list.
- When you run it, if the blue “Windows protected your PC” screen appears: click More info, then Run anyway.
- With the portable ZIP: before extracting it, right-click the file, choose Properties, tick Unblock at the bottom of the General tab, then OK. Extract it and run 1 - START KORR.
- If Windows 11 Smart App Control blocks the program, no button lets you through. Use the web app on this page or the browser extension instead: they need no installation and work offline.
What the installer does: it installs in your user folder, without administrator rights, connects to no server on the Internet, and uninstalls from Windows Settings like any other program. Publisher stated in the file: Geoffrey Giner.
Check the file: the SHA-256 fingerprint of every file is shown on the release page. To compare, open PowerShell in your Downloads folder and type Get-FileHash .\Korr-Setup-*.exe.
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.
Works in Edge too, which installs extensions from the Chrome Web Store.
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