## How to use the ATAN function

*Article updated on March 27, 2018*

The ATAN function calculates the arctangent of a number. The returned angle is in radians between -pi/2 to pi/2.

### Excel Function Syntax

ATAN(*number*)

### Arguments

number |
Required. The tangent of the angle. |

### Comments

Use the DEGREES function to convert radians to degrees.

=DEGREES(ATAN(-1))

How to use the DEGREES function

The DEGREES function calculates degrees from radians. Formula in cell C3: =DEGREES(B3) Excel Function Syntax DEGREES(angle) Arguments angle Required. The […]

### Functions in 'Math and trigonometry'

The ATAN function function is one of many functions in the 'Math and trigonometry' category.