Pythagorean Theorem Calculator

Calculate the missing side of a right triangle using the Pythagorean theorem a² + b² = c².

Side a (Leg)Leave blank for unknown side

Side b (Leg)

Side c (Hypotenuse)

Missing Side

Area of Triangle

Is Right Triangle?

Perimeter

How It Works

In a right triangle, the square of the hypotenuse (c) equals the sum of the squares of the other two sides (a and b). Enter any two sides and leave the unknown blank — the calculator will solve for the missing side.

a² + b² = c² | c = √(a² + b²) | a = √(c² − b²)

About this Calculator

The Pythagorean Theorem Calculator is a free, easy-to-use tool for theorem, triangle, hypotenuse. Simply enter your values and get instant, accurate results — no signup, no ads, no tracking. All calculations run locally in your browser, so your data stays completely private.

Privacy Note: All calculations are performed locally in your browser. No data is ever sent to a server or third party.