Pythagorean Theorem Calculator
Solve for any missing side of a right triangle.
Enter your values
ⓘ Live results
Results
- Hypotenuse c
- 5
- Leg a
- 3
- Leg b
- 4
- Area
- 6
- Angles
- 36.87° and 53.13°
Working
- 1c = √(3² + 4²) = 5
Quick answer
In a right triangle a² + b² = c², where c is the hypotenuse opposite the right angle.
a² + b² = c²
How to use the Pythagorean Theorem Calculator
- 1Enter any two sides.
- 2Leave the unknown side blank.
- 3Read the missing side, area and angles.
Frequently asked questions
What is a Pythagorean triple?
Three whole numbers satisfying a² + b² = c², like 3-4-5, 5-12-13 and 8-15-17.
Does it work on non-right triangles?
No. Use the law of cosines, which reduces to Pythagoras when the angle is exactly 90°.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.