Math enthusiasts around the world, from college students to rocket scientists, celebrate Pi Day, which is March 14 or 3/14 — the first three digits of an infinite number with many practical uses. Many people will mark the day with a slice of pie — sweet,

National Pi Day 2025 brings pizza and pie deals nationwide, with discounts like $3.14 pizzas and freebies from major chains.

Pi Day is Friday, March 14 and Blaze Pizza, Marco's Pizza and others are celebrating with deals and discounts on pie and pizza.