Solve a right triangle for missing sides, angles, area, and perimeter from any two known measurements.
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How to use
Enter any two known values — two sides, or one side and one acute angle — and the calculator will solve for the remaining sides, angles, area, and perimeter.
Also in General
Geometry
The right triangle calculator finds all missing sides, acute angles, area, and perimeter from any two known values — two sides, or one side and one angle.
Given two sides, the third is found via the Pythagorean theorem (a squared + b squared = c squared). Angles are found using inverse trigonometric functions.
Given one side and one acute angle, the other angle is 90 minus the given angle. The remaining sides are found using sine, cosine, or tangent ratios.
The calculator assumes a valid right triangle. If inputs are inconsistent (e.g. a leg longer than the hypotenuse), an error is shown.
Frequently asked questions
Two measurements: either two sides, or one side and one acute angle. The right angle is already known.
The longest side of a right triangle, opposite the 90-degree angle. It equals the square root of the sum of the squares of the two legs.
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