Run peristent JavaScript and CSS code snippets on any website.
Users
25
−2 in 30 days
Rating
3.7 / 5
−1.33 in 30 days
Ratings
3
+1 in 30 days
Store rank
#141K
#117K among extensions
Version
1.0.0
updated 15 Jan 2026
Users
monthly, 9 months
Latest, 18 Oct 2026:25 usersMove the mouse over the chart for any month
Ratings count
monthly, 9 months
Latest, 18 Oct 2026:3 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About JS and CSS snippets for web
Snippet Injector lets you add your own code to websites based on URL rules. Create and manage snippets that run automatically when pages load. Perfect for developers, QA engineers, power users, and anyone who wants to customize websites or test scripts.
Key Features
Inject JavaScript or CSS: Run code in the page’s main world or isolated CSS safely.
Flexible URL rules: Apply snippets to all websites, a single domain, exact URLs, or custom regular expressions.
Enable or disable snippets: Turn snippets on or off without deleting them.
Persistent across reloads: Snippets automatically run when pages reload.
Dynamic page support: Works with modern single-page apps (SPAs) and iframe-based sites.
Built-in code editor: Write and edit snippets directly in the popup using a clean editor interface.
Who It’s For
- Web developers testing or debugging code.
- QA engineers automating workflows.
- Power users customizing web apps or dashboards.
- Anyone looking for a lightweight alternative to Tampermonkey.
Permissions & Privacy
- Tabs: Check the active tab URL to run matching snippets.
- Storage: Save your snippets and settings locally.
- Scripting: Inject JavaScript and CSS into websites safely.
- No data is collected, all code runs locally, and your snippets stay private.
- Take control of your browser. Customize websites your way with Snippet Injector.