Type the digits of π from memory, one at a time. The card shows "3." and every digit you get right. The first wrong digit ends the run.
There is no time limit. The run stops at 300 digits after the decimal point.
How to play
The clock starts at your first keystroke and counts up. There is no time limit.
Type the next digit. The quiz checks each digit as you type it. You do not press Enter.
A correct digit joins the row on the card. The first wrong digit ends the run, and the quiz shows what the digit should have been.
Your score is the number of correct digits in a row. Reaching 300 clears the run.
A full 300 ranks by time: the fastest player is first.
Give up ends the run early and shows your results.
Select "Review answers" on the result screen to see how far you got, and the digits that came next.
What counts in this quiz
The first 300 digits of π after the decimal point: 3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510 …
The card groups the digits in fives, so you can keep your place.
What's not included, and why
The leading 3 is not typed and does not count. The score counts digits after the decimal point.
Good to know
The record for reciting π from memory is more than 70,000 digits, set by Rajveer Meena in 2015 over about 10 hours.
π has been computed to more than 100 trillion digits. For any real calculation, 40 digits give the circumference of the observable universe to the width of a hydrogen atom.