The Powder Toy

The classic open-source physics sandbox — sand, water, fire, pressure, heat and a few hundred other materials — compiled from C++ to WebAssembly and running natively in your browser. No install, no plugins, no server doing the work.

Physics Sandbox

Loads about 6 MB of WebAssembly on demand. Best with a mouse and keyboard — the controls assume a desktop.

Click inside the simulation before typing — the game only receives keys while it has focus.

What it is

The Powder Toy was created by Stanislaw K. Skowronek — "Skylark" — in 2008, and has been developed by the open-source community ever since. Every pixel is a particle with its own temperature, pressure, velocity and reactions. Set fire to wood, boil water into steam, melt metal, build working logic circuits, then blow it all up.

This is the real game — version 100.1, built from upstream source — not a reimplementation. Your creations save to your browser's local storage and survive a reload.

Controls

  • Draw / erase LeftRight click
  • Brush size Scroll[]
  • Pause physics Space
  • Step one frame F
  • Undo / redo Ctrl+ZCtrl+Y
  • Straight line Shift+drag
  • Filled rectangle Ctrl+drag
  • Sample material Alt+click
  • Zoom tool Z
  • Help F1

Source & credits

The Powder Toy is free software under the GPL v3. Created by Stanislaw K. Skowronek and the TPT contributors — this page runs an unmodified upstream build, cross-compiled to WebAssembly with Emscripten.

Complete corresponding source: github.com/The-Powder-Toy/The-Powder-Toy  ·  Official site and save gallery: powdertoy.co.uk

Online features — the save gallery, accounts, publishing — are disabled in this build. The TPT servers only accept those requests from their own site, so everything here runs entirely offline in your browser.