Right Triangle Calculator

Free online right triangle calculator. Enter any two sides to instantly find the third side, area, perimeter, and all angles using the Pythagorean theorem.

Quick Examples

A = ? B = ? C = ? α β

About Right Triangle Calculator

A clean, visual right triangle calculator based on the Pythagorean theorem. Enter any two sides of a right triangle to instantly calculate the third side, plus area, perimeter, and all angles. Perfect for students, carpenters, engineers, and DIYers.

Features

FAQ

What is the Pythagorean theorem?

The Pythagorean theorem states that in a right triangle, the square of the hypotenuse (the side opposite the right angle) equals the sum of the squares of the other two sides: a² + b² = c².

Can I calculate any side?

Yes! Enter any two sides and the calculator will find the third. Enter A and B to find C, A and C to find B, or B and C to find A.

What are Pythagorean triples?

Pythagorean triples are sets of three positive integers that satisfy the Pythagorean theorem. Common examples include 3-4-5, 5-12-13, and 8-15-17.

Is this calculator free?

Yes, completely free. No registration, no ads, no limits. All calculations happen in your browser.