ScratchJS
ScratchJS is an extension for Scratch that adds a load of new blocks to the editor.
Get ScratchJS
Drag this link to your bookmarks bar: ScratchJS
Or, copy the following code into a new bookmark:
How it works
ScratchJS works as a bookmarklet, which is a special bookmark that
runs code instead of visiting a website.
This extension works by injecting a script into the page that
registers an extension into the Scratch editor.
How to contribute!
We're currently looking for developers that know JavaScript to help us develop ScratchJS with new blocks and features!
Join our Scratch studio to help or contribute on GitHubStatus
The extension currently has 210+ blocks and 23 categories. as of April 2026
Categories
- Math
- Constants
- Booleans
- Strings
- Special reporters
- Core JS Blocks
- Console
- Control Flow
- Storage
- Utilities
- Temporary Variables
- Arrays
- Objects
- Data
- Games
- Date and Time
- Statistics
- Browser
- Color
- Input
- Timing
- Unicode
- And More...
Quick Links
FAQ
What is ScratchJS?
ScratchJS is an extension for Scratch that adds new blocks to the editor.
The extension isn't loading.
Try refreshing the page and clicking the bookmark again. If this
doesn't work, check your internet connection.
If you're still having issues, there could be something like a filter
blocking the extension.
If you can, whitelist jsdelivr.net on your browser or
filter, and make sure that javascript: URLs are allowed.
The blocks aren't working.
Try the actions above, and if the blocks still are not working, there
could be an issue with the extension.
If so, please report it on our
GitHub issues page.
Thanks to everybody who has helped us develop ScratchJS!