📐 Pythagorean Theorem Calculator – Solve Right Triangles Instantly

Need to find the missing side of a right triangle? This free Pythagorean Theorem Calculator makes it easy to solve for the hypotenuse or a leg with just two known side lengths. Whether you’re studying geometry or solving real-world problems, this tool gives you accurate results instantly.

Side A:

Side B:

⚙️ How to Use the Pythagorean Theorem Calculator

You can use this calculator in just three easy steps.

First, enter the two known sides of the triangle.
Next, choose whether you’re solving for the hypotenuse or a leg.
Finally, click “Calculate” and get your result instantly.

The tool uses the classic formula: a² + b² = c². You can enter whole numbers or decimals, and the missing side will be calculated immediately.

📐 What Is the Pythagorean Theorem?

The Pythagorean Theorem is a foundational concept in geometry. It relates the lengths of the three sides of a right triangle: the two legs and the hypotenuse. The formula — a² + b² = c² — helps you calculate one missing side if the other two are known.

Named after the ancient Greek mathematician Pythagoras, this formula is used everywhere from school math classes to real-world problems in architecture, navigation, and engineering.

💡 Real-World Uses for the Pythagorean Theorem

There are many practical uses for this formula. For example:

Measuring the diagonal of a TV or computer monitor
Calculating ladder height needed against a wall
Solving roof pitch or slope problems in construction
Determining the shortest path between two points

Because this calculator eliminates manual math, it’s perfect for professionals and students alike.

🔗 Related Tools

Hypotenuse Calculator – Instantly find the longest side of any right triangle.
Area of a Triangle Calculator – Calculate triangle area using base/height or side lengths.
Explore more tools – Browse our complete collection of free calculators and converters.

If you’re working with right triangles, this Pythagorean Theorem Calculator will help you get fast, accurate results — no formulas needed.