Square Calculator

What Is a Square Calculator?

A square is a four-sided shape with all sides equal and every angle a perfect right angle — one of the simplest and most common shapes in everyday life, from floor tiles to picture frames. This calculator finds the area, perimeter, and diagonal length from a single side measurement.

How to Use This Square Calculator

1. Measure one side of the square — since all sides are equal, that's all you need.
2. Enter the side length into the field above.
3. Click Calculate to instantly get the area, perimeter, and diagonal.

Formula

• Area = a²
• Perimeter = 4 × a
• Diagonal = a × √2

Worked Example

A square tile has a side of 30 cm. Area = 30² = 900 cm². Perimeter = 4 × 30 = 120 cm. Diagonal = 30 × √2 ≈ 42.43 cm.