Inverse Trig Calculator
Find the angle from a sine, cosine, or tangent value.
Inputs
arcsin/arccos accept values in [-1, 1]
Result
Enter a value and click calculate.
About inverse trig functions
Inverse trig functions answer: "what angle has this sine/cosine/tangent value?"
Standard ranges: arcsin returns angles in [-90°, 90°], arccos returns [0°, 180°], and arctan returns (-90°, 90°). These are the principal values.
Frequently Asked Questions
What does arcsin(x) actually return?▾
It returns the angle whose sine is x. For arcsin and arccos, x must be in [-1, 1]. arctan accepts any real number.
Why is the output range limited?▾
Inverse trig functions return the principal value: arcsin in [-90°, 90°], arccos in [0°, 180°], and arctan in (-90°, 90°). This makes them true functions (one output per input).
When are inverse trig functions used?▾
They appear constantly in physics (finding angles from force or velocity components), navigation, computer graphics, and any time you need to recover an angle from a ratio.
Is sin⁻¹ the same as 1/sin?▾
No — that is a notational trap. sin⁻¹(x) means arcsin(x), the inverse function. The reciprocal 1/sin(x) is csc(x).