RADIANS function

The RADIANS function in Excel is used to convert an angle measured in degrees to radians. Since Excel works with angles in radians for most of its trigonometric functions, the RADIANS function is useful when you need to use degrees but Excel’s functions require radians.

Syntax

=RADIANS(angle)

• angle: The angle in degrees that you want to convert to radians.

Description

• The RADIANS function converts the given angle (in degrees) to its equivalent value in radians.
• The formula to convert degrees to radians is: $$\text{radians} = \text{degrees} \times \frac{\pi}{180}$$
• If the angle is in radians, you can convert it to degrees using the DEGREES function.

Example 1: Converting Degrees to Radians

To convert 180 degrees to radians:

=RADIANS(180)

Result:

The result is 3.14159265358979, which is equivalent to $\pi$ radians.

Example 2: Using RADIANS with Trigonometric Functions

If you want to calculate the sine of 45 degrees, first convert 45 degrees to radians:

=SIN(RADIANS(45))

Result:

The result is approximately 0.7071, which is the sine of 45 degrees.

Example 3: Using Cell References

If cell A1 contains an angle in degrees, you can convert it to radians like this:

=RADIANS(A1)

Result:

The result will be the angle in A1 converted to radians.

Usage Notes

• The RADIANS function is typically used in trigonometric calculations, as Excel’s trigonometric functions like SIN, COS, and TAN expect angles to be in radians.
• The function does not round the result; it provides the full precision of the conversion.