Hypotenuse Calculator

Pythagoras's theorem states that in any right-angled triangle, the square of the hypotenuse equals the sum of the squares of the other two sides: a squared plus b squared equals c squared, where c is the hypotenuse. This relationship lets you find any one side when you know the other two, and this calculator handles all three versions of the problem. If you know both legs a and b, it calculates the hypotenuse c = the square root of (a squared plus b squared). If you know the hypotenuse c and one leg a, it finds the missing leg b = the square root of (c squared minus a squared). The same works if you know c and b and want a. To use the calculator, enter two known side lengths and leave the third field blank. The calculator automatically detects which two you have provided, solves for the missing one, and also returns the triangle's perimeter, its area (half the base times height for a right triangle), and the two non-right angles in degrees. The default example uses a=3 and b=4, which gives the hypotenuse c=5, one of the most famous results in all of mathematics, the 3-4-5 Pythagorean triple. This tool is useful for students at every level, builders checking whether a corner is truly square (a 3-4-5 check), surveyors calculating distances, and anyone who needs the third side of a right triangle. Results are for reference only.

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