Arc Length Calculator

Calculate arc length instantly using radius and central angle. Supports both degrees and radians with real-time results.

Input Values

010

Arc Diagram

rrθs
Radius (r)
Arc Length (s)
Angle (θ)

Results

Arc Length (s)
0
s = rθ
Radius (r)
5.0000
input
Angle (degrees)
0°
θ°
Angle (radians)
0 rad
θ rad

Arc Length Formulas

s = rθ
Arc length (radians)
s = rθ° × π/180
Arc length (degrees)
θ rad = θ° × π/180
Degrees to radians

About Arc Length

Arc length is the distance along the curved line forming the arc. It is a portion of the circumference of a circle, determined by the radius and the central angle that subtends the arc.

Key Concepts

  • Arc: A portion of a circle's circumference
  • Central Angle: Angle at the center of the circle
  • Radians: Angle where arc length equals radius
  • Full circle: 360° = 2π radians

How to Use

  1. Enter the radius of your circle
  2. Enter the central angle
  3. Toggle between degrees and radians
  4. View the arc length result instantly

Common Examples

  • A 90° arc (quarter circle) with radius 10: s = 10 × π/2 15.71
  • A 180° arc (semicircle) with radius 5: s = 5 × π 15.71
  • A 360° arc (full circle) equals the circumference: s = 2πr