Pythagorean Theorem Calculator
Find the hypotenuse, area, and perimeter of a right triangle from its two perpendicular sides.
Your result
Review your calculated values below.
Ready when you are.
Choose Calculate to see your result.
How to use this calculator
- Enter your values in the labeled fields, keeping the displayed units.
- Choose Calculate or press Enter in a single-line field.
- Review the result and the assumptions below before using it.
Formula and method
Hypotenuse c = √(a² + b²). Area = a × b / 2. Perimeter = a + b + c.
Worked example
A right triangle with legs 3 and 4 has hypotenuse 5, area 6, and perimeter 12.
What the result assumes
Enter both lengths in the same unit. The angle between these sides must be exactly 90 degrees.
Common question
Can this solve a triangle that is not right-angled?
No. The Pythagorean theorem applies only to right triangles; use the general triangle calculator for other cases.