Tampermonkey is the world's most popular userscript manager.

Tampermonkey promo image
What is Tampermonkey?

Tampermonkey is a popular Firefox add-on by Jan Biniok. This add-on has 599,664 daily active users and a good user rating of 4.71. The latest version, 4.18.1, was updated 4 months ago.

Stats date:
Version: 4.18.1 (Last updated: 2022-11-15)
Creation date: 2016-02-01
Weekly download count: 28,859
Firefox on Android: Yes
Manifest version: 2
  • notifications
  • tabs
  • idle
  • webNavigation
  • webRequest
  • webRequestBlocking
  • unlimitedStorage
  • storage
  • contextMenus
  • clipboardWrite
  • See more
Size: 1.50M
Risk impact: High risk impact
Risk likelihood: Low risk likelihood
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Other platforms

Tampermonkey BETA
Tampermonkey BETA (v4.19.6180)
4,427 629,677
Tampermonkey BETA
Tampermonkey BETA (v4.19.6180)
69 224,347
Tampermonkey is the most popular userscript manager, with over 10 million weekly users. It's available for Chrome, Microsoft Edge, Safari, Opera Next and Firefox. 

Tampermonkey makes it very easy to manage your userscripts and provides features like a clear overview over the running scripts, a built-in editor, ZIP-based import and export (Google Drive, Dropbox, OneDrive), automatic update checks and also browser and cloud storage based synchronization. And finally it's compatible to Greasemonkey up to version 3.x with experimental 4.x support.

Note: If you want to install the more often updated BETA version, then you can get it from here: https://tampermonkey.net/?browser=firefox
Risk impact

Tampermonkey requires a number of risky permissions that can potentially harm your browser and steal your data. Exercise caution when installing this add-on. Review carefully before installing. We recommend that you only install Tampermonkey if you trust the publisher.

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, bypass your security settings, and access your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Risk likelihood

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

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, especially ones with higher risk impact and/or higher risk likelihood.

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User reviews

by daishixu, 2023-03-26

by SD3, 2023-03-25
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