Square Calculator

Compute the area, perimeter and diagonal of a square from a single side length.

Square Calculator

Compute the area, perimeter and diagonal of a square from a single side length.

Please enter a valid value.

Result

How to use the Square Calculator

  1. Enter the side length.
  2. Click Calculate.

Formula

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

Example

Side = 7: Area = 49. Perimeter = 28. Diagonal ≈ 9.899.

Step-by-step calculation

  1. Area: 7² = 49.
  2. Perimeter: 4 × 7 = 28.
  3. Diagonal: 7 × √2 ≈ 7 × 1.414 = 9.899.

Real-world uses

  • Tile and flooring calculations.
  • Pixel and grid measurements.
  • Box and cube surface area.

Common mistakes

  • Squaring the side instead of multiplying by 4 for perimeter.
  • Confusing side with diagonal.
  • Forgetting the square root symbol.

Frequently asked questions

Why is the diagonal a√2?
By Pythagorean theorem: d² = a² + a² = 2a², so d = a√2.
Can a square have a diagonal equal to its side?
No. The diagonal is always about 41.4% longer than the side.
How do I find the side from the area?
Side = √Area. For area 49: √49 = 7.

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