Pi Day 2025 Article. On pi day (march 14), nasa reminded us why we need only a small slice of the irrational number's infinite decimal places to explain most of the known universe. What's the state of raspberry pi in 2025?

When is pi day in 2025? You may already know all about the mathematical constant pi (π) and how it can be used to calculate things like the circumference of a circle or the volume of a sphere.