Arc

A piece of a circle's circumference — measured by angle or by length.

An arc is a piece of a circle's circumference.

Stretch the radius

radius
3.5

diameter
7.0

circumference
21.99

area
38.48

angle: 110°

arc length ≈ 6.72

Arc length

L = r \cdot θ (θ in r a d ian s)

Try it

Arc length of a 90° arc on a circle radius 10

θ = π/2. L = 10 × π/2 = 5π ≈ 15.7.