Pythagorean Theorem Calculator
Hypotenuse of a right triangle from two legs.
How it works
c = √(a² + b²)
Pythagorean theorem: the sum of the squares of the legs equals the square of the hypotenuse. 3-4-5 is the classic integer triple.
FAQ
Is the hypotenuse always the longest?
Yes. The hypotenuse faces the right angle and is longer than either leg in any non-degenerate right triangle.
Worked example
Legs 6 and 8: c = √(36+64) = 10.
This is the classic 3-4-5 triangle scaled by two.
Notes and limitations
a² + b² = c² holds only for right triangles, with c the hypotenuse opposite the right angle. For other triangles use the law of cosines.