Angle Of Right Triangle
Find the missing angle of a right triangle using opposite and adjacent sides. Free online right triangle angle calculator with instant results and hypotenuse computation.
About This Calculator
This free online angle of right triangle calculator finds the missing acute angle using the lengths of the opposite and adjacent sides. It uses the inverse tangent (arctan) function: \u03b8 = arctan(opposite/adjacent). The hypotenuse and both side lengths are also shown.
This tool is ideal for trigonometry students, construction professionals measuring roof pitches or stair angles, and anyone who needs to compute an angle from two known side lengths in a right triangle.
Frequently Asked Questions
How do you find an angle of a right triangle?
Use inverse tangent: angle = arctan(opposite/adjacent). Enter the lengths of the opposite and adjacent sides to get the angle in degrees.
What is the relationship between angles in a right triangle?
A right triangle has one 90\u00b0 angle and two acute angles that sum to 90\u00b0. If you find one acute angle, subtract it from 90\u00b0 to get the other.
Does this calculator also find the hypotenuse?
Yes, it computes the hypotenuse using the Pythagorean theorem: c = \u221a(opposite\u00b2 + adjacent\u00b2), along with displaying both side lengths and the angle.
What units are used for the angle?
The angle is displayed in degrees (\u00b0) with two decimal places of precision.
Is this tool free?
Yes, all calculators on Calculy are completely free to use with no registration required.