Arc Length Calculator

Calculate the arc length of a circle sector using the radius and central angle (degrees or radians).

Enter radius and angle.

Arc Length Formula

Arc Length = (θ/360) × 2πr (degrees)
Arc Length = θ × r (radians)
Example: r = 10, θ = 90°
Arc = (90/360) × 2π(10) = 0.25 × 62.83 = 15.71

Last updated: 2026-08-08