# Excel RADIANS Function

Summary

The Excel RADIANS function converts degrees to radians. For example, =RADIANS(180) returns 3.1415 or the value of π (pi).

Purpose

Converts degrees into radians

Return value

Radians

Syntax

=RADIANS (angle)

Arguments

**angle**- Angle in degrees to convert to radians.

Usage notes

The RADIANS function takes an angle in degrees and converts it to radians. Radians measure angles using the radius of a circle. For example, to convert a 45 degree angle to radians the formula is:

=RADIANS(45) // Returns 0.785 or π/4

### Explanation

A radian is equal to the amount of rotation required to travel one radius along the circumference of the circle, as seen in the image above. A full-rotation or 360° in radians is equal to the value of 2π. A half-rotation or 180° in radians is equal to the value of geometric constant π (pi).

### Notes

- To convert radians to degrees, see the DEGREES function.
- A full-rotation (360°) in radians is equal to 6.283 or 2π
- A half-rotation (180°) in radians is equal to 3.142 or π (pi).