Manifest V3 · Chrome, Firefox, Edge

Run scripts on
any website

SnapMonkey is a lightweight userscript manager that lets you install, manage, and execute .user.js scripts to customize any website.

Free. No account required.

SnapMonkey — Script Store

YouTube Enhancer

Layout improvements, download, dark mode

26.6K installs

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Telegram Downloader

Download media from private channels

199.7K installs

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Reddit Enhancement

Expand images, keyboard nav, filters

84.2K installs

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GitHub Dark Mode

Custom dark theme for GitHub

12.1K installs

Install

Everything you need

A full-featured userscript manager built on modern web standards.

Script Store

Browse and install scripts from GreasyFork directly inside the extension. Search, sort, and preview before installing.

Code Editor

Built-in editor with syntax highlighting, dark and light themes, adjustable font size, and keyboard shortcuts.

Manifest V3

Built on the latest extension platform. Future-proof, secure, and approved for Chrome Web Store.

Cross-Browser

One extension for Chrome, Firefox, and Edge. Same features, same interface everywhere.

Full GM_ API

GM_getValue, GM_xmlhttpRequest, GM_addStyle, GM_notification, and all standard APIs. Works with any userscript.

Export & Import

Back up all scripts, values, and settings to a JSON file. Restore or transfer between browsers.

How it works

Three steps to customize any website.

01

Install SnapMonkey

Add the extension to your browser from Chrome Web Store, Firefox Add-ons, or Edge Add-ons.

02

Find a script

Browse the built-in GreasyFork store or paste any .user.js URL. Review permissions before installing.

03

Scripts run automatically

Visit any matching website and your scripts execute automatically. Toggle scripts on or off from the toolbar popup.

What people use it for

Remove ads Dark mode everywhere Download media Customize YouTube Auto-fill forms Bypass paywalls Reddit enhancements Price trackers Keyboard shortcuts Custom CSS Twitter tweaks GitHub improvements

Start customizing the web

Free, lightweight, and private. No accounts, no tracking, no data collection.