Question: Why does the internet say that farts travel at 10 ft/s?
Short answer: Because the internet is wrong.
Long answer: Among the websites that are concerned with the topic, there is near-total agreement that the speed of farts is 10 feet per second. A quick survey of the top hits on Google finds some version of this statement on sites such as How Stuff Works, Seventeen Magazine, Today online, India Today, Muscle & Fitness, Quora, South China Morning Post, University of Melbourne, and the Edison, NJ School District, to name just a few.
The speed of farts is not 10 feet per second. It’s not even close to that. Careful measurements reveal an average fart speed of 0.01 feet per second, which means that the Internet’s favorite figure is off by a factor of 1000. While a certain amount of misinformation about cutting-edge science is understandable, this seems like an unusual amount of confusion. Perhaps it is only exceeded by certain creationists, whose belief about the age of the earth is off by a factor of 1,000,000. But these “young-earth” creationists are a minority, even among creationists, while the misconception about fart speed appears in otherwise reputable, mainstream sources.
We were curious to know where this strange belief came from. The spread of misinformation online follows the same mathematical progression as the spread of infectious diseases, so it seemed worth the effort to understand this phenomenon.
For the most part, the websites noted above do not list a source for their claims about fart speed. There are a few exceptions though, and these turned out to be useful. We found that three of the sites attributed the claim to an article posted in 2018 on something called oddee.com, which in turn identifies its source: a website called Facts on Farts.
Now, Facts on Farts was apparently published in 1998, and it is an absolute gem of a site. The author is someone named Brenna Lorenz, a Professor of Geology who clearly spent a lot of time researching farts and answering questions about them. Critically, and in keeping with Professor Lorenz’s scholarly approach, the site does not say that farts travel at 10 feet/second. So for the present purposes, it is a dead end.
Several other sites attributed the 10 feet/second claim to an article from NBC News, which involves an interview with a physician about different bodily functions. The doctor does not actually say anything about fart velocity, but rather the statement is appended to the end of the article, along with a few other bits of information about farts. Again there is no source for the claim, but the article was posted in 2008, which predates all the other ones listed above. So we thought it might plausibly be the original source.
However, we noticed that the NBC site and many of the others used an odd phrase: “Farts have been clocked at a speed of 10 feet per second.” When we searched on this phrase, we uncovered a number of posts on messaging boards from the early 2000s. It appears that a meme comprised of a list of seemingly silly “Fart Facts” was circulating back then — it appears in 2006 on a blog called “Confessions of a Dumb, White Guy” and around the same time on a blog called “Rola Family Values” and in 2007 at the site Ball-Pythons.net, again under the heading “Fart Facts”. By the way, Ball-pythons.net is billed as the “friendliest online community for ALL your herping needs!”
Traveling a bit farther back in time, we arrive at the first available instance of the “Fart Facts” meme: Someone named Puffy posted it in July 2004 on a site called RedZone (“for Reds fans, by Reds fans”).
With all due respect to Puffy, it seemed unlikely that he or she was the source, so we turned to the Internet Archive, which revealed that the identical set of “Fart Facts” was published on a website called mistupid.com (“The Online Knowledge Magazine”), sometime before Aug. 4, 2004.
After spending several weeks in the local library, we came upon a book called “Who Cut the Cheese? A Cultural History of the Fart,” by Jim Dawson. On page 10, one finds the claim, “Once out in the world, the fart darts away from ‘ground zero’ at a speed that’s been clocked at ten feet per second.” This book was first published in 1999.
So, a likely scenario is that this false claim about fart speed originated in Dawson’s book and subsequently mutated into the “Fart Facts” list that first appeared on the mistupid page; from there it circulated for a number of years in messaging boards, and then infected the NBC news article, which acted as a kind of superspreading event. It is now everywhere and impossible to get rid of.