Pi Day 2024 Meaning. Pi day is a day devoted to celebrating pi, the irrational number (approximately 3.14) that results from dividing the length of the circumference of a circle by the length of its diameter. It's all about celebrating the number pi, which is 3.14.
The numbers in the date (3/14) match the first three digits of the. Math enthusiasts around the world, from college kids to rocket scientists, celebrate pi day on thursday, which is march 14 or 3/14 — the first three digits of an infinite number.