Sine Calculator
Compute the sine of an angle, in degrees or radians.
Calculator
Use the Sine Calculator
Result
—
Formula
sin(θ)
Step-by-step
- 1
Enter the angle
Any numeric value.
- 2
Pick the unit
Degrees or radians.
Worked example
Example input: angle: 30, mode: deg
Result: 0.5
Related tools
- Cosine Calculator
cos(θ).
- Tangent Calculator
tan(θ).
- Pythagorean Theorem
Right-triangle math.
Frequently asked questions
What is the sine of 30 degrees?
Exactly 0.5, matching the classic 30-60-90 triangle where the side opposite the 30° angle is half the hypotenuse.
Should I enter degrees or radians?
The calculator defaults to degrees. Switch the unit selector to radians when the angle comes from a formula — for example, entering π/6 in radians mode also gives 0.5.
What does sine actually measure?
In a right triangle, sine is the ratio of the side opposite the angle to the hypotenuse. As the angle sweeps through a full turn, the output stays between −1 and 1.
What is sin of 90 degrees?
Exactly 1 — the maximum of the sine wave. On the unit circle, 90° points straight up where the opposite side equals the hypotenuse, so sin = 1. Angles above 90° start falling back down, which is why the wave turns again.