Right Triangle Calculator (Pythagorean Theorem)
Enter the two legs of a right triangle to calculate its hypotenuse, area and perimeter using the Pythagorean theorem.
Right Triangle Calculator (Pythagorean Theorem)
Calculate the hypotenuse, area and perimeter of a right triangle from its two legs.
The Pythagorean theorem states that in a right triangle, the square of the hypotenuse equals the sum of the squares of the other two sides. This calculator uses it to find the hypotenuse from two legs, then calculates the triangle’s area and perimeter.
Example
- With the default values shown above, this calculator returns: Hypotenuse ≈ 5.000; Area ≈ 6.000; Perimeter ≈ 12.000.
Frequently Asked Questions
What if I know the hypotenuse and one leg instead?
Rearrange the Pythagorean theorem: the missing leg equals the square root of (hypotenuse squared minus the known leg squared). This calculator is set up for the two-legs-known case.
Does this work for any triangle?
No — the Pythagorean theorem only applies to right triangles, where one angle is exactly 90 degrees between the two legs entered.