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Grammalecte

grammalecte.net

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Spec score 9.0 #3 of 26 in AI Grammar Checkers

What it is

Grammalecte is free, GPL 3 open-source software for checking French grammar and typography. It detects punctuation, spacing, typography, repeated words, hyphenation, capitalization, agreement, conjugation, confusions, and pleonasms. Users can enable or disable error categories and choose Classic, 1990 Reform, or All Variants spelling dictionaries, with Classic selected by default. Suggestions use several mechanisms, and an OCR option can detect errors in text produced by optical character recognition. A formatter addresses recurring errors and restructures text; its conjugator covers about 8,000 verbs. Grammalecte is available as a desktop app and browser extension on Linux, macOS, and Windows. Listed integrations include LibreOffice or OpenOffice, Firefox, Thunderbird, a command-line interface, server, and Python package. The FAQ says writing is analyzed locally, with no data collected or text transmitted. The maker says the checker does not perform semantic analysis, can miss mistakes, and may produce false positives. There is currently no version compatible with Chrome’s new extension API.

Spec sheet

What it does
Grammalecte is an open-source French grammar and typography checker for LibreOffice, OpenOffice, Firefox, Thunderbird and related software.Read 15 Oct 2026 · grammalecte.net
Purpose
Grammalecte is an open-source grammar and typography checker dedicated to French.Read 8 Oct 2026 · grammalecte.net
Free plan
YesRead 20 Sep 2026 · grammalecte.net
Integrations
Official integrations include LibreOffice, OpenOffice, Firefox and Thunderbird; community plugins exist for Sublime Text, Vim, Emacs, GEdit, Pluma and Sigil.Read 15 Oct 2026 · grammalecte.net
Support
The maker directs Writer users to LibreOffice or OpenOffice help forums and Firefox or Thunderbird users to the Mozfr forum.Read 8 Oct 2026 · grammalecte.net
Browser extension
YesRead 20 Sep 2026 · grammalecte.net
Chrome limitation
The official site says there is currently no Grammalecte version compatible with Chrome’s new extension API.Read 15 Oct 2026 · grammalecte.net
Chrome support
The maker says there is currently no Grammalecte version compatible with Chrome’s new extension API.Read 8 Oct 2026 · grammalecte.net
CLI capabilities
Debian’s man page documents file checking, JSON error output, text formatting, personal dictionaries, suggestions, rule listing and option toggles.Read 15 Oct 2026 · manpages.debian.org
Conjugator
Its conjugator covers about 8,000 verbs contained in the dictionary.Read 15 Oct 2026 · grammalecte.net
Current version
The official site lists version 2.3.0, released 15 December 2025.Read 15 Oct 2026 · grammalecte.net
Custom dictionary
A lexical editor lets users create a personal dictionary.Read 15 Oct 2026 · grammalecte.net
Data handling
The FAQ says Grammalecte collects no data, analyzes writing on the user's computer, and transmits no text.Read 8 Oct 2026 · grammalecte.net
Desktop app
YesRead 20 Sep 2026 · grammalecte.net
Developer distribution
The project publishes a command-line interface, server and Python package requiring Python 3.7 or newer.Read 15 Oct 2026 · grammalecte.net
Dictionaries
It supplies Classic, 1990 Reform and All Variants French spelling dictionaries, with Classic selected by default.Read 15 Oct 2026 · grammalecte.net
Error detection
The checker covers punctuation, spacing, typography, redundancy, hyphenation, capitalization, gender and number agreement, conjugation, homonyms, false friends, pleonasms and optional OCR errors.Read 15 Oct 2026 · grammalecte.net
False-positive strategy
Its stated design goal is to minimize false alerts and remain silent when an error cannot be identified confidently.Read 15 Oct 2026 · grammalecte.net
Firefox privacy
The official site says the Firefox module sends no information online.Read 15 Oct 2026 · grammalecte.net
Firefox security
The Firefox add-on is signed, its code is checked by Mozilla, and the maker says it sends no information online.Read 8 Oct 2026 · grammalecte.net
Grammar controls
Users can enable or disable individual categories of grammatical checks.Read 15 Oct 2026 · grammalecte.net
Implementation
The core is written primarily in Python and translated into JavaScript for browser and Thunderbird extensions.Read 15 Oct 2026 · grammalecte.net
Known limitations
The official site warns that false positives cannot be eliminated, overlapping Writer errors can apply a correction to both regions, and superscript or subscript text may be disturbed.Read 15 Oct 2026 · grammalecte.net
Languages supported
1Read 20 Sep 2026 · grammalecte.net
Lexicographer
The lexicographer identifies the grammatical nature of the word at the cursor.Read 15 Oct 2026 · grammalecte.net
LibreOffice requirements
The current LibreOffice extension targets LibreOffice 6.4 and newer; older builds cover earlier LibreOffice and OpenOffice releases.Read 15 Oct 2026 · grammalecte.net
LibreOffice tools
The LibreOffice integration includes a word counter and a tool for changing Writer’s author field.Read 15 Oct 2026 · grammalecte.net
Licence
The public source repository identifies Grammalecte as GPL-3.0 licensed.Read 15 Oct 2026 · github.com
License and price
Grammalecte is described as free open-source software distributed under the GPL 3 license.Read 8 Oct 2026 · grammalecte.net
Limit: formatted text compatibility
Chrome-Stats reports complaints that formatted fields such as Overleaf can suffer corruption, duplication or reordered text.Read 15 Oct 2026 · chrome-stats.com
Limit: interface and support
La Fabrique du Net describes the interface as austere, says support is mainly community-based, and reports weaker performance on complex or long technical texts.Read 15 Oct 2026 · lafabriquedunet.fr
Limitations
The FAQ says the checker does not perform semantic analysis and cannot detect every mistake; false positives can still occur.Read 8 Oct 2026 · grammalecte.net
Linux requirements
Linux LibreOffice users need a Python-UNO bridge such as libreoffice-pyuno, python3-uno or openoffice-python-uno.Read 15 Oct 2026 · grammalecte.net
Local processing
The FAQ says analysis runs on the user’s computer, with no text transmitted, stored or collected.Read 15 Oct 2026 · grammalecte.net
Maker founded
Algoo says it has been rooted in free software since its creation in 2015.Read 15 Oct 2026 · algoo.fr
Maker headquarters
LinkedIn lists Algoo’s headquarters at 340 rue de l’Eygala, 38430 Moirans, France.Read 15 Oct 2026 · fr.linkedin.com
Maker size
Algoo’s official site says its team has 11 collaborators.Read 15 Oct 2026 · algoo.fr
Notable news
LinuxFr reports that version 2.3 added rules, removed false positives and bugs, improved suggestions, updated dictionaries and transferred future stewardship to Algoo.Read 15 Oct 2026 · linuxfr.org
OCR option
An option can detect errors from optical character recognition.Read 8 Oct 2026 · grammalecte.net
Praise: configurability
Clubic says the tool is fluid, complete and easy to use, with more configurable formatting and typography rules than many competitors.Read 15 Oct 2026 · clubic.com
Praise: French accuracy
Chrome-Stats’ review summary says users repeatedly praise accurate French grammar detection and consider the tool useful or indispensable.Read 15 Oct 2026 · chrome-stats.com
Praise: privacy and French focus
La Fabrique du Net praises its French specialization, free GPL distribution, LibreOffice and Firefox integration, and local processing without third-party transmission.Read 15 Oct 2026 · lafabriquedunet.fr
Rating on Chrome-Stats
4.27 out of 5 from 100 reviewsRead 15 Oct 2026 · chrome-stats.com
Rating on Clubic
6.2 out of 10 from 9 ratingsRead 15 Oct 2026 · clubic.com
Rating on Firefox Add-ons
4.3 out of 5 from 103 reviewsRead 15 Oct 2026 · addons.mozilla.org
Rating on Thunderbird Add-ons
4 out of 5 from 21 reviewsRead 15 Oct 2026 · services.addons.thunderbird.net
Semantic limitation
The FAQ states that Grammalecte performs no semantic analysis and cannot detect meaning errors such as confusing two grammatically valid homonyms.Read 15 Oct 2026 · grammalecte.net
Style suggestions
YesRead 20 Sep 2026 · grammalecte.net
Suggestion engine
Grammalecte includes several mechanisms for generating correction suggestions.Read 15 Oct 2026 · grammalecte.net
Suggestions
The product includes several suggestion mechanisms and lets users enable or disable error-search categories.Read 8 Oct 2026 · grammalecte.net
Text formatter
The formatter batch-corrects recurring typographic problems and offers text-restructuring options.Read 15 Oct 2026 · grammalecte.net
Thunderbird security
The maker says the Thunderbird add-on is unsigned and can be installed before its code has been checked; it sends no information online.Read 8 Oct 2026 · grammalecte.net
Writing tools
Its text formatter can fix recurring errors and restructure text, and its conjugator covers about 8,000 verbs.Read 8 Oct 2026 · grammalecte.net

Plans and prices

Free Free Open-source software · French grammar and typography correction · donations requested Read 15 Oct 2026 · grammalecte.net
Grammalecte Free Open-source software; French grammar and typography correction Read 8 Oct 2026 · grammalecte.net

Every Grammalecte plan and price →

Strong points and limits

Strong points

  • Free GPL 3 open-source software
  • Checks many French grammar and typography categories
  • Analyzes writing locally without transmitting text
  • Includes formatter and conjugator for about 8,000 verbs
  • Supports multiple spelling dictionaries

Limits

  • Dedicated to French only
  • Does not perform semantic analysis
  • Cannot detect every mistake and may show false positives
  • No version supports Chrome’s new extension API

Who it suits

Grammalecte suits French-language writers who want local grammar and typography checking on desktop or supported extensions. It also fits users needing LibreOffice, Firefox, Thunderbird, command-line, server, or Python access.

Verdict

Grammalecte offers broad French correction with local processing and several integration formats. Its language scope, semantic-analysis limitation, and current Chrome extension incompatibility should guide selection.

Where Specifiction places it

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