Reviewed by CalcMulti Editorial Team·Last updated: ·← Geometry Hub
A right triangle has one 90° angle. The side opposite the right angle is the hypotenuse (always the longest side). The other two sides are called legs. The Pythagorean theorem states that a² + b² = c², where c is the hypotenuse.
Given any two pieces of information (two sides, one side and one acute angle, or the hypotenuse and area), you can find all remaining sides and angles. The acute angles of a right triangle always sum to 90°.
Enter any two known values below — the calculator finds all missing sides, angles, area, and perimeter using the Pythagorean theorem and trigonometric ratios (sin, cos, tan).
a² + b² = c²
½bh, Heron's, and two sides + angle methods
Law of Cosines CalculatorSolve any triangle — not just right triangles
Law of Sines CalculatorAAS, ASA, SSA triangle solving
Perimeter CalculatorPerimeter of triangles and all shapes
Sector Area CalculatorArea and arc length of circular sectors
Polygon Area CalculatorRegular polygons with 3–12 sides
This calculator is for educational purposes only and does not constitute professional advice. Results are based on standard mathematical formulas. Always verify critical calculations with a qualified professional before making important decisions.