For math lovers around the world, March 14 is a holiday, "Pi Day." That's because the date — 3/14 — is also the beginning of the decimal expansion of the world's best-known irrational number: ...

A former student of mine wrote to ask about π. Specifically, he wondered how, whenever someone announces they've calculated the first 100 billion digits or whatever (actually, the current record is 13 ...

This whole series of posts was motivated by a question from a former student of mine: whenever someone announces they've computed a bunch of digits of π, how do we know it's correct? As I pointed out ...

Daniel Ullman does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...

After thousands of years of trying, mathematicians are still working out the number known as pi or "π". We typically think of pi as approximately 3.14 but the most successful attempt to calculate it ...

Whether using 3.141 or the record-holding 314 trillion–digit calculation announced in December 2025 by Storage Review Lab director Kevin O'Brien, every representation of π is still an approximation.

See more of our trusted coverage when you search. Prefer Newsweek on Google to see more of our trusted coverage when you search. Pi Day is celebrated every year on March 14—when the date can be ...

Oh dear—π day 2016 has gone by and I still haven’t memorized p in what I used to call the ‘‘elementary’’ way that I invented some decades ago. Somebody recently suggested the much better name ...

Some people can't remember a nine-digit Social Security number without a prompt; Siva Natarajan can recite hundreds of consecutive digits for π, the irrational number that never ends and never repeats ...