ASIN Function
Returns the angle (in radians) whose sine is the supplied number.
Syntax
Parameters
| Parameter | Description | Required |
|---|---|---|
| number | The sine of the angle you want, which must be a real number between -1 and 1 inclusive. | Required |
Basic Example
Find the angle whose sine is 1
=ASIN(1)The arcsine of 1 is π/2 radians (90°), the angle whose sine equals 1.
Advanced Examples
Example 1: Convert the result to degrees
Need the angle in degrees.Wrap ASIN in DEGREES.
=DEGREES(ASIN(0.5))Example 2: Angle from a sine ratio
Given opposite/hypotenuse = 0.7071.Use the ratio directly.
=DEGREES(ASIN(0.707106781))How ASIN Works
ASIN is the inverse of SIN. For an input x in [-1, 1] it returns the unique angle θ in [-π/2, π/2] (radians) such that sin(θ) = x.
Important Notes & Limitations
The argument must be between -1 and 1; otherwise the function returns #NUM!.
The result is in radians; apply DEGREES for degree output.
ASIN returns only the principal value, limited to the [-π/2, π/2] range.
Common Errors & Fixes
#NUM!The argument is outside the -1 to 1 range.Fix: Provide a valid sine value between -1 and 1.
#VALUE!The argument is non-numeric text.Fix: Supply a numeric value or a numeric cell reference.
Download Practice File
ASIN
asinPractice ASIN with Real Data
Download a sample CSV file with pre-populated data and practice exercises for the ASIN function. Works in both Excel and Google Sheets.
File format: CSV (comma-separated values) - opens in Excel, Google Sheets, and all spreadsheet apps