Grammarly: AI Writing and Grammar Checker App

Name: Grammarly: AI Writing and Grammar Checker App
Rating: 4.1057 (3170 reviews)
Author: Grammarly

Improve your writing with Grammarly's AI assistance. Get spell check, grammar check, generative AI, and more in one tool. Real-time suggestions for improving tone and clarity help ensure your writing makes the impression you want.

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Grammarly is a comprehensive AI-powered writing assistant that offers real-time grammar, spelling, punctuation, and clarity suggestions directly in your browser. Beyond basic proofreading, it helps refine your tone, style, and word choice to communicate more effectively. With built-in generative AI features, Grammarly assists in creating drafts, replies, and ideas wherever you write, including Google Docs, email, and social media.

Available in free and Pro versions, Grammarly supports users from students to professionals. It includes handy tools like auto-citations in APA, MLA, and Chicago styles, tone detection, advanced sentence rewrites, and vocabulary enhancements, all designed to elevate your writing quality. Trusted by millions, Grammarly seamlessly integrates with your online workflows for confident and polished writing every time.

Add-on

By:

Grammarly

Daily users:

649,990 -4,887

Rating:

4.11

(3,170) 1 new ratings

Version:

8.931.0 Last updated: 2025-05-14

Version code:

5943562

Creation date:

2014-12-17

Risk:

Permissions:

http://*/*
https://*/*
tabs
notifications
cookies
identity
storage

Size:

38.01MB

URLs:

Full description:

Source:

Firefox Browser Add-ons

Data ingested on:

2025-07-08

Ranking

# 23 ▼ 1

Other rankings

#7 in Language Support

#12 in Social & Communication

#20 in Other extensions ▼ 1

#1 in ai writing keyword 59

#1 in writing tools keyword 57

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Other platforms

Grammarly: AI Writing and Grammar Checker App (v14.1243.0)

38,000,000 4.51

(42,769)

Grammarly-AI Writing Assistant (v2.85.52863)

52,586,823 4.06

(249,020)

Grammarly: AI Writing and Grammar Checker App (v14.1111.0)

15,601,989 3.90

(1,123)

User reviews

Users find Grammarly for Firefox helpful and effective when functional, especially appreciating its AI writing features. However, multiple reviews report persistent bugs including login problems, UI failures, syncing issues, and poor performance on certain platforms like Google Docs. Many users note the generative AI does not work on Firefox, and the extension sometimes makes incorrect corrections. Overall, while it was previously valued, current versions on Firefox frequently fail to operate reliably, leading to frustration and diminished utility.

Pros

Helpful and awesome when it works
Previously useful and good product for grammar correction

Cons

Frequent login prompts and failure to stay logged in
Buggy behavior such as UI malfunctions and syncing issues
Does not work properly or at all with Google Docs and some other platforms
Generative AI features do not work on Firefox version
Performance issues causing slowdowns and inaccurate corrections

Recent reviews

by Le*****, 2025-07-02

by Fi*****, 2025-06-30

by el*****, 2025-06-26

View all user reviews ›

Extension safety

Risk impact

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Grammarly: AI Writing and Grammar Checker App requires a lot of sensitive permissions. 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

Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Browser Add-ons, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

Grammarly: AI Writing and Grammar Checker App has earned a fairly good reputation and likely can be trusted.

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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