Complete Guide to Pythagorean Theorem — Formula, Examples & More

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1. What is the Pythagorean Theorem?

The Pythagorean Theorem is a free online tool that helps you calculate calculate the hypotenuse of any right triangle. free, instant, no sign-up required. It is part of CalcHub Pro's collection of 50+ free calculators covering finance, health, math, science, engineering, and everyday calculations.

This calculator is designed for students, professionals, and everyday users who need accurate results quickly without installing any software or creating an account.

2. How to Use It on CalcHub Pro

Go to the Pythagorean Theorem page
Enter your values in the input fields
Click the Calculate button
Your result appears instantly below the button

There is no sign-up, no download, and no payment required. The calculator works on any device — desktop, tablet, or mobile.

3. The Formula

c = √(a² + b²)

This is the standard formula used by professionals and institutions worldwide

4. Worked Example

Step-by-step example

a=3, b=4 → c = √25 = 5 (the classic 3-4-5 triangle)

5. Security and Privacy

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Your calculation history is never logged or tracked

6. Related Tools

7. Frequently Asked Questions

What is a right triangle?

A triangle with one 90-degree angle.

Can I find a or b if I know c?

Yes: a = √(c² − b²). Rearrange the formula.

Are Pythagorean triples common?

Yes — 3-4-5, 5-12-13, 8-15-17 are common integer examples.

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Pythagorean Theorem — Complete Guide