# Length of an Arc

How to find the length of an arc: formula, example, and its solution.

## Formula

*l* = 2*πr*⋅(θ/360)*l*: length of an arc*π*: 3.141592...*r*: radius of the arc*θ*: measure of the arc's central angle

(= measure of the arc)

2*πr*: circumference of the circle

θ/360: ratio of (arc)/(circumference)

## Example

*r* = 6, *θ* = 120*l* = 2*π*⋅6⋅(120/360)