Greasemonkey

Name: Greasemonkey
Rating: 4.1904 (1292 reviews)
Author: Anthony Lieuallen

By: Anthony Lieuallen

Customize the way a web page displays or behaves, by using small bits of JavaScript.

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Features & Capabilities

Greasemonkey is a powerful Chrome extension that enables users to customize the appearance and behavior of web pages through small JavaScript scripts. Whether you want to modify layouts, add new functionalities, or automate repetitive tasks, Greasemonkey provides a flexible platform to personalize your browsing experience.

Users can create their own scripts or utilize a vast collection of existing ones available on the Greasemonkey wiki. This extension empowers you to enhance your favorite websites to better suit your needs without requiring advanced development skills. For support and tutorials, the Greasemonkey manual and script hosting resources are a great starting point.

User Growth & Download Statistics

Add-on Developer Tools Programming

By:

Daily users:

Rating:

Version:

4.14 Last updated: 2026-06-08

Version code:

6288866

Creation date:

2005-05-20

Risk:

Permissions:

Size:

592.90KB

URLs:

Website

Full description:

Source:

Firefox Add-ons Store

Data ingested on:

2026-06-22

Compare stats and ranking:

Ranking

# 110 ▲ 1

Other rankings

#23 in Other extensions

#12 in money keyword 17 ▲ 1

#31 in base keyword 14 ▲ 1

#34 in keyword keyword 57 ▼ 1

#36 in javascript keyword 45 ▼ 1

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For Developers

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Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.

Developed by:

Anthony Lieuallen

Firefox Add-ons Store

https://addons.mozilla.org/firefox/addon/greasemonkey/

Website:

http://greasespot.net/

User Reviews

User reviews for the Greasemonkey Firefox add-on are mixed; some users appreciate that the extension works instantly and as intended, praising the developers' efforts. However, others report that it does not work for them, considering it a waste of time.

Pros

Extension works immediately as expected.
Good work by the developers.

Cons

Not working for some users.

Recent reviews

by Di*****, 2026-06-07

by lo*****, 2026-05-17

I've tried several alternatives and this one is by far the best. Straightforward and does the job perfectly.

by Je*****, 2026-05-17

View all user reviews ›

Is Greasemonkey Safe?

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.

Greasemonkey 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 Add-ons Store, 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.

Greasemonkey has earned a fairly good reputation and likely can be trusted.

Risk likelihood analysis details

High This extension was recently updated in the past month. New updates may not be stable or safe.
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