Right Triangle Calculator
Angles, Sides & Trig ⚡
Enter any two values to find all sides and angles of a right-angled triangle, including sine, cosine and tangent.
Choose which 2 values you know:
Enter any two values to find all sides and angles of a right-angled triangle, including sine, cosine and tangent.
Choose which 2 values you know:
sin(α) = opposite ÷ hypotenuse = b ÷ c
cos(α) = adjacent ÷ hypotenuse = a ÷ c
tan(α) = opposite ÷ adjacent = b ÷ a
The three angles always sum to 180°, with the right angle = 90°, so α + β = 90°.
What is SOH CAH TOA?
A memory aid for trigonometric ratios: Sine = Opposite/Hypotenuse, Cosine = Adjacent/Hypotenuse, Tangent = Opposite/Adjacent.
Can I find angles from sides?
Yes — enter two sides and the calculator finds all angles using inverse trig functions (arcsin, arccos, arctan).
What is the difference between degrees and radians?
A full circle is 360° or 2π radians. This calculator uses degrees — the most common unit for everyday use.