Instantly find area, perimeter, and diagonal from any side length
Square Calculator
Area
25
m²
Perimeter
20
m
Diagonal
7.071068
m
Formulas used
where s = side length = 5 m
Visual Reference
Quick Reference
Use this free square calculator to instantly compute the area, perimeter, and diagonal of any square from its side length. Supports multiple units including millimeters, centimeters, meters, inches, feet, and yards. Whether you are planning a room layout, a garden plot, or solving a geometry problem, this tool delivers accurate results with the formulas shown.
The area of a square equals the side length multiplied by itself: Area = s². For example, a square with a side of 5 m has an area of 25 m².
The diagonal of a square is found using the Pythagorean theorem: d = s × √2, where s is the side length. This gives approximately 1.4142 times the side length.
Since all four sides of a square are equal, the perimeter is simply 4 × s. A square with a side of 3 ft has a perimeter of 12 ft.
Yes. This calculator supports millimeters, centimeters, meters, kilometers, inches, feet, and yards. Select your preferred unit from the dropdown before entering the side length.