The Science Of How Fast A Fart Is

The nerds at Asap Science went Good Will Hunting all over a whiteboard to figure out that “the smelly part” of a fart can theoretically fly at 243 meters per second. Don’t worry, the added complexities of reality help slow the stank down. But the breakdown is actually pretty interesting! You know, from an engineering perspective.

“Farts are like snowflakes,” this video explains, but are generally composed of 59 percent nitrogen, 21 percent hydrogen, 9 percent carbon dioxide, 7 percent methane, 3 percent oxygen and only one percent of what sinks– mainly something called “skatole.”


NASA explains that the molecules of gases “are in constant, random motion and frequently collide with each other and with the walls of any container” and that kinetic theory dictates these impacts determine pressure.

So assuming a fart is at body temperature, and plugging the molar mass (the mass of a substance divided by the amount of it) into the kinetic theory of gases, Asap Science figures that fart-stink should be able to fly at a blistering 243 meters per second.

However; your toxic buttcloud actually ends up moving a lot more slowly due to air resistance, wind, and physical objects the smell could scatter off. So Asap Science couldn’t quite find a laser-accurate radar gun for your farts, but they did teach us some interesting stuff about how gases move.

And hey, who else always thought methane was the smelly part?

For more hot #fart content, check out Jason’s breakdown of how poop-air might be used as propulsion in space?

Jalopnik Staffer from 2013 to 2020, now Editor-In-Chief at Car Bibles



How bad is one at science to go from smart feller to fart smeller...