Square Perimeter and Area Calculator
Enter the side length of a square to calculate its area, perimeter and diagonal.
Square Perimeter and Area Calculator
Calculate the area, perimeter and diagonal length of a square from its side length.
This calculator provides an estimate for general informational purposes only. It is not a substitute for professional financial, mechanical or engineering advice.
A square's area is its side squared, its perimeter is four times its side, and its diagonal follows from the Pythagorean theorem as the side length times the square root of 2.
Example
- With the default values shown above, this calculator returns: Area ≈ 64.00; Perimeter ≈ 32.00; Diagonal ≈ 11.31.
Frequently Asked Questions
What are the formulas?
Area = Side². Perimeter = 4 × Side. Diagonal = Side × √2 (≈ 1.4142136).
How is the diagonal derived?
By the Pythagorean theorem, a square's diagonal splits it into two right triangles with legs equal to the side length, giving a diagonal of side × √2.