Inverse Sine (arcsin) Calculator
The Inverse Sine (arcsin) Calculator finds the angle whose sine equals a value between -1 and 1, shown in both degrees and radians. The formula used is: arcsin(x) = the angle θ such that sin(θ) = x, with the result in [-90°, 90°].
Formula
arcsin(x) = the angle θ such that sin(θ) = x, result in [−90°, 90°]
Example Calculation
Inputs
- Value (−1 to 1): 0.5
arcsin(0.5) = 30° (π/6 ≈ 0.5236 radians), because sin(30°) = 0.5.
Frequently asked questions
What is arcsin?
Arcsin, the inverse sine, returns the angle whose sine equals the value you enter. It reverses the sine function.
What input range is allowed?
Only values from -1 to 1, since sine never produces a result outside that range.
What is the output range?
The principal value runs from -90° to 90° (-π/2 to π/2 radians).
How do I get radians instead of degrees?
This calculator shows both. To convert manually, multiply the degree result by π/180.
Why does arcsin(0.5) equal 30°?
Because sin(30°) = 0.5, so the angle whose sine is 0.5 is 30°.