The Physics of Super Mario Bros.

How the 1985 game moves Mario, read out of its 6502 code. Mario here runs on a frame-exact copy of that code; the music and sound are the game's own sound engine.

Super Mario Physics

A guided tour of how Mario runs, skids, jumps and falls, with every number taken from the original game's code. Turn your sound on.

vol

Horizontal speed px/frame 0.000

Vertical speed, up is + px/frame 0.000

Sources: doppelganger's annotated disassembly of Super Mario Bros. (SMBDIS.ASM) and the game's ROM. The engine on this page (physics.js) was checked against the real ROM in MAME on 18 scripted runs: every speed, position and timer byte matched on every frame (51,160 values). The sound is the game's own SoundEngine routine running on a small 6502 emulator, checked against MAME's APU register log. One frame is 1/60.0988 s, the NTSC NES rate.