Enter the two legs of a right triangle to get the hypotenuse, both angles, area and perimeter.
How the right triangle calculator works
This calculator solves a right triangle from its two legs. It returns the hypotenuse, the two non-right angles, the area and the perimeter.
It combines the Pythagorean theorem with basic trigonometry.
The default scenario, worked through
On the values this calculator opens with, the hypotenuse is 5. Underneath, Angle A comes out at 36.9° and Angle B at 53.1°. Change any field and every figure updates as you type.
Step by step
- Enter the length of leg a.
- Enter the length of leg b.
- Read the hypotenuse, angles and area.
How the number is calculated
hypotenuse = √(a² + b²)
angle A = arctan(a ÷ b) · area = ½ × a × b
Frequently asked questions
How do I solve a right triangle?
With two sides you get the third from Pythagoras, and the angles from inverse trig functions like arctan.
What are the angle rules?
The two non-right angles add to 90°, since all three angles sum to 180° and one is the right angle.
How is the area found?
Half the product of the two legs — they act as base and height.