When Is Pi Day 2026?
Pi Day 2026
That was 124 days ago.
Rule: always March 14. Check any other date’s weekday
About Pi Day in 2026
March 14 is Pi Day because, written in US month/day format, the date reads 3.14 — the first three digits of the mathematical constant pi (the ratio of a circle's circumference to its diameter).
Pi itself is an irrational number, meaning its decimal digits never terminate or repeat; computers have calculated it to trillions of digits, far beyond any practical mathematical need.
Pi's digits have no repeating pattern, a property mathematicians call irrationality, which is part of why memorization contests for its digits remain a genuine challenge.
Pi Day in 2026 — March 14th, a Saturday already off-cycle.
Pi Day, 2026 — day 73 of 2026: ISO week 11 (Q1), 292 left.
Pi Day, 2026: next is Sunday, March 14th; prior was Friday, March 14th.
Related dates
Other years
Other March holidays in 2026
Browse every holiday and year on the When Is index.