5-12-13 Right Triangle Hypotenuse
With legs 5 and 12, the hypotenuse is exactly 13 — the 5-12-13 Pythagorean triple.
How to use this tool
- Enter side a and side b in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your hypotenuse c and the full breakdown beneath it.
The 5-12-13 triple is a fundamental Pythagorean set: sides 5 and 12 produce a hypotenuse of exactly 13.
Frequently asked questions
- What is the Pythagorean theorem?
- For a right triangle with legs a and b, the hypotenuse c satisfies a² + b² = c². Classic example: 3² + 4² = 9 + 16 = 25 = 5².