About the Pythagorean Theorem Calculator

A right-triangle side calculator with a live diagram, in your browser.

What it is

The Pythagorean Theorem Calculator solves aยฒ + bยฒ = cยฒ for whichever side of a right triangle is missing, given the other two. It draws a scaled diagram of the triangle and highlights the side being solved for, making it easy to see the geometry behind the math.

Features

Solve any side

Enter any two sides โ€” both legs, or a leg and the hypotenuse.

Live diagram

A scaled right-triangle diagram updates as you type, with the solved side highlighted.

Area included

See the triangle's area alongside the three side lengths.

Step-by-step working

See the exact formula and substitution used to reach the result.

Ready to use it?

Free, no sign-up required.

Open the Pythagorean Theorem Calculator