📐 Pythagorean Theorem Calculator
Find the missing side or hypotenuse of a right triangle instantly.
Enter Two Known Sides
Leave the side you want to calculate completely blank.
What is the Pythagorean Theorem?
The Pythagorean Theorem is a fundamental mathematical rule that applies only to right-angled triangles (triangles where one angle is exactly 90 degrees). It states that the square of the hypotenuse (the longest side opposite the right angle) is equal to the sum of the squares of the other two sides.
- a = Side A (Leg)
- b = Side B (Leg)
- c = Side C (Hypotenuse, the longest side)
How to Find the Hypotenuse (c)
If you know both the shorter legs (a and b), you can find the hypotenuse (c) using this formula:
c = √(a² + b²)
Example: If a = 3 and b = 4:
c = √(3² + 4²)
c = √(9 + 16)
c = √25 = 5
How to Find a Missing Leg (a or b)
If you know the hypotenuse (c) and one leg (let's say b), you can rearrange the formula to solve for the missing leg (a):
a = √(c² - b²)