How Many Digits Of Pi You Have To Have Memorized To Be Special

Today is Pi Day — the day each year, March 14, that follows the first three digits of pi (3.14). And this year’s Pi Day is a special one: Since — in the U.S. — the date is represented as 3/14/15, we have the first five digits of pi on the calendar.

That’s news for some people. When it comes to how many digits of pi people know by heart, the majority only know 3.14. Which is fine! Unless you’re building a bridge, that’s the most you will really need to know.

I asked SurveyMonkey Audience to put out a poll to see how far people could get reciting the infinite digits of pi. Of 941 respondents, 836 attempted to name the digits after the decimal point. This is how far they got:

LEVEL OF PRECISION PERCENTAGE OF RESPONDENTS
3.1 73
3.14 64
3.141 33
3.1415 26
3.14159 19
3.141592 12
3.1415926 10
3.14159265 7
3.141592653 5

If you can get to the first 3 after the decimal point, you’re in the top 5 percent of pi memorizers. I asked the people who got that far to keep going, and most tapped out shortly after.

The biggest drop came after “3.14,” as respondents who got that far made it to “3.141” only about 52 percent of the time.

And that’s fine!

NASA employees can probably get away with knowing only the first six digits after the decimal point. Also, we have calculators for when we need a few more digits, TI-89s for when those calculators are insufficient and Wolfram Alpha for when we reduce those calculators to a smoking, melted mess.

Maybe after the highly anticipated apocalypse, the guys at the Large Hadron Collider will be happy to have that dude who memorized tens of thousands of pi digits around, but for now, he’s just got a weird hobby. Knowing pi is strictly a performative act, like people who readily volunteer their SAT score or high school completion percentage.

But, uh, happy holidays.

Walt Hickey was FiveThirtyEight’s chief culture writer.

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