Grammar and Spell Checker - LanguageTool

With this extension you can check text with the free style and grammar checker LanguageTool. It finds many errors that a simple spell checker cannot detect, like mixing up there/their, a/an, or repeating a word.

LanguageTool: Grammar & Spell Checker for Firefox

"Grammar and Spell Checker - LanguageTool" is a powerful Firefox add-on that checks your text for grammar, spelling, and style errors across the web. It supports over 25 languages and provides instant feedback, helping you elevate your writing with suggestions for concise phrasing, synonyms, and more. Privacy-focused, it requires no registration, ensuring your data remains secure. Ideal for both non-native and native speakers, LanguageTool enhances your writing skills effortlessly.
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View on Firefox Browser Add-ons

Add-on stats

Manifest V3
Daily users: 402,822
-8,182
Rating: 4.69
(4,320)
11 new ratings
Version: 8.14.3 (Last updated: 2025-01-14)
Version code: 5867646
Creation date: 2016-06-10
Weekly download count: 10,028
Firefox on Android: No
Permissions:
  • activeTab
  • storage
  • contextMenus
  • alarms
Size: 13.44M
Full description: See detailed description

Ranking

# 47
Other rankings
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Other platforms

Not available on Chrome
Not available on Android
AI Grammar Checker & Paraphraser – LanguageTool (v8.14.3)
730,059 4.80 (545)

User reviews

These summaries are automatically generated weekly using AI based on recent user reviews. Firefox Browser Add-ons does not verify user reviews, so some user reviews may be inaccurate, spammy, or outdated.
Pros
  • Works reliably and effectively for spell checking and grammar correction.
  • Helpful for users with visual impairments or difficulties in typing accurately.
  • Positive feedback regarding its performance and utility as a writing assistant.
Cons
  • Requires extensive permissions, which raises privacy concerns about data access.
  • Limited free usage with a restriction on the number of words that can be checked without a pro version.
Most mentioned
  • Effective spell and grammar checker functionality.
  • Concerns regarding data privacy and the extensive permissions required.
  • Issues with compatibility with certain applications, particularly Next.js, which can cause errors.
User reviews
by Rojo, 2025-03-09
by Kenaimike, 2025-03-09
by Firefox user 16290193, 2025-03-07
View all user reviews

Add-on safety

Risk impact

Grammar and Spell Checker - LanguageTool requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details
  • Critical Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
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Risk likelihood

We don't have sufficient data to confidently determine the risk likelihood of Grammar and Spell Checker - LanguageTool. Use it at your own risk.

Risk likelihood analysis details
  • Medium This extension was updated in the past 3 months. New updates may not be stable or safe.
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