Which two values can I start from?

Any of: two legs, one leg plus the hypotenuse, one leg plus an acute angle, or the hypotenuse plus an acute angle. The right angle is always assumed at vertex C.

What trig identities does it use?

It uses the Pythagorean theorem (a² + b² = c²) for sides and SOHCAHTOA — sin, cos and tan ratios — to recover the angles. The two acute angles always sum to 90 degrees.

Is my data sent anywhere?

No. Every calculation runs locally in your browser with no network requests.

Right Triangle Trig Solver

Solve any right triangle from two known values — sides and angles.

Solve any right triangle

Give this tool any two known values and it solves the rest of a right triangle: the missing sides via the Pythagorean theorem, both acute angles via SOHCAHTOA, plus the area and perimeter.

The right angle sits at vertex C, with angle A opposite leg a and angle B opposite leg b. Everything is computed in your browser — nothing is uploaded.