Square Calculator
Calculate the area, perimeter, and diagonal of a square from its side length.
How it works
- 1Area = side² — multiply the side length by itself to get the area enclosed by the square.
- 2Perimeter = 4 · side — the total boundary length is four times the side.
- 3Diagonal = side · √2 — by the Pythagorean theorem, the corner-to-corner distance equals the side scaled by √2.
Use cases
- Estimating flooring or tile for a square room.
- Calculating fencing or framing material for a square plot.
- Verifying geometry homework answers for square properties.
Frequently asked questions
What is the formula for the diagonal of a square?
The diagonal equals the side length times √2 (≈ 1.4142), which follows from the Pythagorean theorem applied to the right triangle formed by two sides and the diagonal.
How is a square different from a rhombus?
A square is a special rhombus where all four interior angles are exactly 90°. Every square is a rhombus, but not every rhombus is a square.
Can I use any unit?
Yes — the calculator is unit-agnostic. Enter the side in any unit; the area is in that unit squared and the perimeter and diagonal in the same linear unit.
Related tools
See all →Calculate the area and perimeter of a rectangle from its width and height, with a labeled diagram.
Calculate the area and circumference of a circle from its radius, with a labeled diagram.
Calculate the area (Heron’s formula) and perimeter of a triangle from its three sides.
Calculate the area and perimeter of a trapezoid from its two parallel sides, height, and legs.