Geometry & Trigonometry
Basic

Diagonal of a Square

Length of the diagonal of a square.

Formula

d=a2d = a\sqrt{2}

Variables

aSide length

Example

A square of side 5 has diagonal d = 5√2 ≈ 7.07.

Did You Know?

A square's diagonal is √2 times its side — the very number the ancient Greeks proved was irrational.

squarediagonalbasics