The Excel ASIN function returns the arcsine (inverse sine) of a number — the angle whose sine is that value. The result is in radians, so wrap it in DEGREES to read it as degrees.
Syntax
| Argument | Description | |
|---|---|---|
number | Required | The sine value, which must be between -1 and 1. ASIN returns the angle in radians, from -π/2 to π/2. |
How to use it
ASIN is the inverse of SIN: give it a sine value and it hands back the angle. That angle comes out in radians, so wrap it in DEGREES() when you want degrees:
The input must lie between -1 and 1 — the full range of the sine function. Feed ASIN a value outside that range and it returns #NUM!. The returned angle always falls between -π/2 and π/2 (−90 to 90 degrees).
Reading the answer in degrees: ASIN always answers in radians. Wrap the whole call in DEGREES() — for example =DEGREES(ASIN(0.5)) returns a clean 30.
Try it: interactive demo
Pick a ASIN example to see the formula and its result.
Practice workbook
Frequently asked questions
Why does ASIN return 1.5708 instead of 90?
=DEGREES(ASIN(1)) — to get 90.What input range does ASIN accept?
-1 and 1 inclusive, because that is the full range of sine. A value outside that range returns #NUM!.What is the difference between ASIN and ASINH?
ASIN is the inverse of the circular sine (angles); ASINH is the inverse of the hyperbolic sine, which accepts any real number.How do I get an angle in degrees from a sine value?
=DEGREES(ASIN(value)). For instance =DEGREES(ASIN(0.5)) returns 30.Master functions like this in one day
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