Pythagorean Theorem Calculator

Find the missing side of a right triangle from the other two sides using the Pythagorean relationship.

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Input

Leave the unknown side blank, enter the other two side lengths, and the calculator will solve the missing value for the right triangle. You will see the result first and the step-by-step solution below.

Input summary

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Step by Step Calculation

a²+b²

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How to use Pythagorean Theorem Calculator

Enter the two known sides of the right triangle, and the calculator will determine the third side from the Pythagorean theorem.

What this calculator is for

This calculator is for right-triangle geometry, construction layout, and coordinate work when one side is missing and the triangle is known to contain a ninety-degree angle.

Tips

Only use this theorem for right triangles.
The hypotenuse is always the longest side and sits opposite the right angle.
Leave exactly one side blank so the calculator knows which measurement to solve.