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Square Calculator

Calculate area, perimeter, and diagonal of a square from its side length.

Dimensions

Updates as you type
Side length
Side (s) ?
cm
0255075100

Formula

A = s 2   P = 4s   d = s √2
A
Area — surface enclosed by the square
P
Perimeter — total length around the square
d
Diagonal — straight line between opposite corners
s
Side — length of one edge (all four are equal)
√2
Square root of 2 — approximately 1.41421356…
Worked example — your numbers
  1. Enter a side length to see each step.
  2. Result:

Every measurement of a square comes from the side length. Once you know the side, the area, perimeter and diagonal follow directly — and any one of those values can be inverted to recover the side.