Enter one angle and one known side of a right triangle to find the other two sides.
How to Use the Trigonometry Calculator
One angle and one known side are enough — the calculator works out the other two sides using the trig ratio that connects them.
SOH-CAH-TOA: Sine is Opposite over Hypotenuse, Cosine is Adjacent over Hypotenuse, Tangent is Opposite over Adjacent. Every calculation this Trigonometry Calculator runs is one of those three ratios, rearranged for whatever you're solving for. Give it one angle and any single known side, and it fills in the other two.
Known hypotenuse: opposite = h × sin(θ), adjacent = h × cos(θ)
Known opposite: hypotenuse = o ÷ sin(θ), adjacent = o ÷ tan(θ)
Known adjacent: hypotenuse = a ÷ cos(θ), opposite = a × tan(θ)The angle has to fall between 0° and 90° — one of the triangle's two acute angles, not the right angle itself. Outside that range you're not describing a standard right triangle anymore, and these ratios stop meaning what they mean here.