Geometry · interactive lab

Pythagorean calculator

Find the hypotenuse or a missing leg, then see the area and both acute angles.

Pythagorean calculatorLIVE EXPLORATION
Change a value to see the connection

Your measurements

In missing-leg mode, the second measurement is the hypotenuse c. Lengths use the same arbitrary unit.

Why it works

a² + b² = c²
    A little question. A clearer picture.

    Pythagorean calculator: common questions

    Wondering about the why? Start here.

    When can I use the Pythagorean theorem?

    Use a² + b² = c² only for a right triangle. The legs a and b meet at 90°, and the hypotenuse c is opposite that right angle. For a triangle without a right angle, use the general triangle solver.

    Solve a general triangle
    How do I calculate a missing leg?

    Subtract the square of the known leg from the square of the hypotenuse, then take the square root: b = √(c² − a²). A hypotenuse of 13 and a known leg of 5 give a missing leg of 12. The hypotenuse must be longer than either leg.

    See the Pythagorean method