Enter two sides of a right triangle to find the third, then review its area, perimeter and acute angles.
01 / CHOOSE A SIDE
02 / KNOWN SIDES
For a right triangle only. The hypotenuse must be longer than either leg. Use matching units for both known sides (up to six decimal places).
03 / YOUR RESULT
04 / FORMULA
For a right triangle, a² + b² = c². Perimeter = a + b + c; area = a × b ÷ 2. Angles are opposite legs a and b; the third angle is 90°.
All triangle calculations stay in your browser.
Enter the values you want to compare; processing happens in your browser.
Adjust optional settings and review validation feedback before relying on the estimate.
Review the formulas and equivalent values, then copy the result you need.
Choose the missing leg or hypotenuse, then enter the two known positive side lengths in the same unit. Check that the hypotenuse is longer than either leg.
Solve all three side cases with the Pythagorean theorem and review extra right-triangle measurements without sending data to a server.
Triangle measurements remain in browser memory and are not uploaded or stored.
For a right triangle, the two legs a and b and hypotenuse c satisfy a² + b² = c².
Enter the positive leg lengths a and b. The hypotenuse is √(a² + b²), measured in the same units.
Yes. Enter the hypotenuse c and the other leg. The missing leg is the square root of c² minus the known leg squared.
The hypotenuse is opposite the right angle and always exceeds either individual leg. Equal or smaller lengths do not form a nondegenerate right triangle.
Area is a × b ÷ 2. Each acute angle is calculated from the ratio of opposite and adjacent legs; the third angle is 90 degrees.
No. The formulas apply to right triangles only. Measurements are processed locally and are not uploaded.