Right Triangle Calculator
Solve any triangle from three known values — SSS, SAS, ASA, AAS or SSA — and get every side, every angle, the area, the perimeter and the heights, with the law of sines and cosines steps written out and a scaled diagram.
Result
This page opens the triangle calculator in the SAS case with a classic right triangle already filled in: legs 3 and 4 with the 90° angle between them. Run it and the law of cosines collapses into the Pythagorean theorem — c = √(3² + 4² − 2·3·4·cos 90°) = √25 = 5 — giving the famous 3-4-5 triangle with acute angles of 36.87° and 53.13°.
Any right triangle works the same way: put your two legs into sides a and b, keep angle C at 90°, and the calculator returns the hypotenuse, both remaining angles, the area (which for a right triangle is simply half the product of the legs), the perimeter and all three heights, with a scaled diagram that marks the right angle with a small square.
If your problem is purely about a² + b² = c² — finding a hypotenuse or a missing leg, ideally as an exact radical like 5√2 — the dedicated Pythagorean theorem calculator on this site shows that exact substitution; this page is the right choice when you also want the angles, the heights and the full triangle picture.