Inverse Trigonometry Calculator
Calculate the angle from a sine, cosine, or tangent value — arcsin, arccos, or arctan.
- Free to use
- Accurate results
- No registration required
- Works on all devices
Enter a value and choose arcsin, arccos, or arctan to calculate the angle (in degrees or radians) that produces that ratio.
For arcsin and arccos, must be between -1 and 1.
Your result
30
Angle
AI explanation
Formula
arcsin, arccos, or arctan of the value, returned in degrees or radiansWorked example
arcsin(0.5)
| Field | Value |
|---|---|
| Value | 0.5 |
| Function | arcsin |
| Result unit | degrees |
| Angle | 30 |
Assumptions
- Arcsine and arccosine are only defined for input values between -1 and 1. Arctangent accepts any real number.
Frequently asked questions
What does "inverse trigonometric function" mean?
It's the reverse operation — instead of finding a ratio from an angle (like sine of 30°), you find the angle that produces a given ratio (like which angle has a sine of 0.5).
Why is arcsin(2) undefined?
Sine values only ever range from -1 to 1, so there's no real angle whose sine is 2 — arcsin and arccos only accept inputs in that range.
Can arctangent accept any number?
Yes — tangent itself can take any real value (approaching infinity near 90°), so arctangent is defined for every real number input.