Reviewed by CalcMulti Editorial Team·Last updated: ·← Geometry Hub
The area of a square is the side length squared: A = s². Because all four sides of a square are equal, you only need one measurement. The perimeter is four times the side: P = 4s. The diagonal — the line connecting opposite corners — equals s√2.
You can also work backwards: given the area, the side length is s = √A. This calculator accepts side length or area and returns all related measurements with step-by-step working.
A = s²
| Side (s) | Area (s²) | Perimeter (4s) | Diagonal (s√2) |
|---|---|---|---|
| 1 | 1 | 4 | 1.414 |
| 2 | 4 | 8 | 2.828 |
| 3 | 9 | 12 | 4.243 |
| 4 | 16 | 16 | 5.657 |
| 5 | 25 | 20 | 7.071 |
| 6 | 36 | 24 | 8.485 |
| 7 | 49 | 28 | 9.899 |
| 8 | 64 | 32 | 11.314 |
| 9 | 81 | 36 | 12.728 |
| 10 | 100 | 40 | 14.142 |
A = l × w — area, perimeter, diagonal of a rectangle
Triangle Area Calculator½bh, Heron's formula, or SAS method
Circle Area CalculatorA = πr² from radius, diameter, or circumference
Perimeter CalculatorPerimeter of rectangles, triangles, circles, polygons
Polygon Area CalculatorArea of regular polygons 3–12 sides
Surface Area Calculator3D shapes — cube, cylinder, sphere, cone
This calculator is for educational purposes only and does not constitute professional advice. Results are based on standard mathematical formulas. Always verify critical calculations with a qualified professional before making important decisions.