phosphorus++ runs your Scratch projects really fast by compiling them to javascript. Try it out by pasting a URL or project ID into the field below or choosing an example.

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Get a link to a web page that automatically runs your project.


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Include the phosphorus player in your web site.

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phosphorus++ is still in development, you can comment on it here


phosphorus was created by Nathan Dinsmore. Its CPS-style compilation and overall design was inspired by Rhys Simpson's sb2.js. It would have more bugs if not for Truman Kilen. It uses the JSZip library, created by Stuart Knightley, David Duponchel, Franz Buchinger, and António Afonso, to read .sb2 files and compressed projects, and the canvg library, created by Gabe Lerner, to render SVGs in <canvas> elements. HTML Games added sound (via javascript wav conversion), various fixes and touch controls for tablets and mobile. Coming soon - compile your project to an APK via webview (as shown on the HTML5 Game to Android App Link)


The source code for phosphorus is available on GitHub. [Zip]