Math Calculators
Pythagorean Theorem Calculator
Find the hypotenuse of a right triangle.
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About the Pythagorean Theorem Calculator
The Pythagorean theorem relates the sides of a right triangle: a² + b² = c². Enter the two legs and the calculator returns the hypotenuse and the triangle's area. It's one of the most-used results in geometry, construction, and navigation — perfect for finding a diagonal or checking a square corner.
How to use the Pythagorean Theorem Calculator
- 01Enter your the two legs (a and b).
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
What is the Pythagorean theorem?
In a right triangle, the square of the hypotenuse equals the sum of the squares of the other two sides: a² + b² = c².
How do I find a missing leg?
Rearrange to a = √(c² − b²). Use the Right Triangle Calculator for full side and angle solving.