switch theme


forkphorus runs Scratch 3, 2, and 1 projects really fast by compiling them to JavaScript. Try it out by pasting a project ID or URL into the field below, selecting a project file, dropping a file on the page, or exploring the examples studio.

Unshared projects are no longer visible

Unshared projects are no longer visible due to Scratch API changes.

For more information and workarounds, visit: https://docs.turbowarp.org/unshared-projects

Report a problem

forkphorus is still in development. Click here to report a problem with this project. You can also comment problems here if you don't have a GitHub account.

Embed this project

Include the forkphorus player in your web site.


Package this project

Get a link to a web page that automatically runs your project. To package to HTML, EXE, APK, or other formats, use the HTML packager.

Package ×


Changes are applied automatically.

Advanced Settings

Help test unfinished features. These require a refresh to apply. Please read this first.

Try out TurboWarp

TurboWarp typically has better performance and compatibility than forkphorus and has an editor. Give it a try, you might like it.


forkphorus is maintained by GarboMuffin and other contributors. It is a fork of Nathan's phosphorus. Its CPS-style compilation was inspired by Rhys's sb2.js. The JSZip library is used to read .sb2 and .sb3 files. The canvg library is used to render SVGs for Scratch 2 projects. The scratch-sb1-converter library is used to support Scratch 1 projects.


The source code for forkphorus is available on GitHub.