A corrector that never flags you wrongly.
Most correctors underline correct text — and for a person with dyslexia, every false alarm rekindles the feeling of failure. Here the rule is reversed : flag nothing until we're sure. That is the project's absolute guard.
100 % offline · no data sent · free · open source · in the app, the « 🩹 Corrector » button
The promise : zero false positives
On its test battery (correct sentences + traps), the corrector flags no error where there is none — measured, not promised. On real encyclopedic French (16,342 sentences), the false-alarm rate dropped to ≈ 2 %; on dyslexic writing, lower still. When it hesitates, it stays silent. The flip side, measured and owned : it catches about half the real errors it targets (≈ 50 % on dyslexic writing; less on hard encyclopedic French), and most of the misses are deliberate abstentions — preferring silence to a false alarm. That's the price of zero false positives : chosen, not suffered.
Who is it for ?
People with dyslexia
Write without being drowned in corrections — and without being corrected wrongly.
Speech therapists
A tool that explains each mistake and suggests remediation, not just “wrong / right”.
Families & teachers
Gentle support at home or in class, free and private.
What it corrects — in context, without knowing the “right” sentence
It reads context to decide what an isolated-word corrector cannot (examples in French — the language it corrects) :
« Les enfant joue dans le jardin et il sont content. » → les enfants jouent… ils sont
« Je doit partir, on ont gagné. » · « le faute » → la faute · « des ami » → amis
And non-words : « fenetre » → fenêtre · « leson » → leçon (underlined, yours to click).
- Grammatical homophones (French) — a/à, son/sont, on/ont, leur/leurs, -é/-er, ce/se, et/est…
- Subject-verb agreement — « les oiseaux chante » → chantent (even with a noun subject)
- Gender & plural — « un maison » → une · « des oiseau » → oiseaux
- Spelling — accents, phonetic errors, non-words
- Type-ahead — as you write, accented completion of the current word, on top of correction
- Remediation — for each mistake, its family and a tip built from the written word; a progress profile that keeps refining
Semi-direct interface : nothing is changed automatically behind your back — you click what you want to apply.
Using it
Browser extension — corrects French
The corrector in any input field (email, social media, forms), offline. On Chrome and Edge.
Read this first: the extension corrects French, and its interface is in French. If you are learning French, that is exactly the point — it is the engine described above, watching what you write anywhere in the browser. To correct English, use the web app below instead — the English side is in beta.
Two clicks. It is on the Chrome Web Store, where it passed Google's review. From Edge, the same page offers “Get”.
No Store on your browser? (Firefox, Chromium, a school machine) — install it by hand
5 min, once, and it is simpler than it sounds :
⬇️ Download the extension (.zip)
- Unzip the downloaded file : right-click → “Extract All”. You get a folder named
extension. - In the browser's address bar, type
chrome://extensions(oredge://extensionson Edge) then Enter. - At the top right of that page, turn on “Developer mode”.
- A “Load unpacked” button appears : click it, then select the
extensionfolder you just unzipped. - (Optional) click the 🧩 icon at the top of the browser, then the pin 📌, to keep the corrector handy.
- Done! Type in any field : a small bar appears with clickable corrections.
🔒 “Developer mode” is safe : it is simply Chrome's option to install an extension without going through the Store. It is the same code as the published one; everything stays on your device, no data is sent.
❓ Nothing shows up? Reload the page where you're writing; and check the extension is enabled in chrome://extensions.
Web app
Paste or type your text; click the 🩹 Corrector button. Nothing leaves your device. The app includes everything : corrector, diagnostic dictation and the cognitive Hangman game it grew from.
⚠️ Beta — the English version is new and updated only occasionally; unlike the French, it isn't human-reviewed. Please double-check as you use it.
Installable (offline, on desktop/mobile) · display settings : light/dark theme, colorblind palette, dyslexia font.
Why trust it
- Measured, not hacked together — every rule is tested on real corpus; ideas that don't hold are rejected and documented.
- Three identical engines — app, extension, and a Python reference, parity-checked automatically.
- Research-grounded — built on Lexique 4 (French lexical database, New, Pallier et al., 2026) and on a typology of dyslexic writing errors (Bodard, 2020).
- Private by design — everything runs on your device; no data is sent.
The detail of the method, measurements and negative results : the research page → — and the engine it grew from : the cognitive Hangman →.
Are you a speech therapist ?
The tool is ready, but it lacks the essential : real field feedback. If you support people with dyslexia and would try it, your view is worth more than any metric. A printable trial sheet already exists.