Right Triangle Calculator

Right Triangle Calculator solves a right triangle from two known values. Enter two sides, a side and an angle, or a side and the area, and it fills in the rest: the third side, both acute angles in degrees and radians, the height to the hypotenuse, the area, the perimeter, the inradius and the circumradius.

What you can enter
• Two legs, a and b, or a leg and the hypotenuse c
• A side and one acute angle, alpha or beta
• The height h, the area S or the perimeter p, together with one side
• Exactly two values: two angles alone cannot size a triangle, and height with perimeter is not accepted

Where it helps
• Roof pitch, ramps and ladders, where an angle and one length are known
• Geometry homework and checking exam answers
• Drafting or surveying a small right-angle layout
• Checking a Pythagorean result by hand

Angles must be less than 90 degrees, since the other acute angle is then the complement. Light and dark theme, 28 languages. The app is supported by banner ads.