🌙 Arc Length Calculator
Calculate the length of a circular arc from the radius and the central angle it subtends.
1
cm
2
degrees
What this calculator finds
An arc length is the distance along the curved edge of a circle between two points, defined by the circle’s radius and the central angle between those points.
The formula
Arc length is s = rθ, where r is the radius and θ is the central angle measured in radians. Since angles are often given in degrees, this calculator first converts degrees to radians using θ = degrees × (π/180). It also reports the area of the pie-slice-shaped sector, A = ½r²θ.
This is useful for geometry problems, engineering layouts, and design work involving curves. This tool is for general educational and planning purposes.
Last reviewed August 2026