This May marks the only time a calendar has a Square Root Day in a 20-year span, with the last one being on April 4, 2016.

A numerical pun, Square Root Day celebrates the alignment of a date into the form of the squaring of a number. For example, May 5, 2025, or 5/5/25, represents 5 x 5 = 25, with the square root of ...

Square root days happen only a few times in a century, and the man who brought the day fame is celebrating his sixth one.

Memorising key square roots and using mental math tricks saves time. Techniques like the nearby perfect square trick and weighted averaging enhance problem-solving skills.