The relationship
Formula
s = rθ (radians) · s = πrθ ÷ 180 (degrees)
For a radius of 10 cm and a central angle of 60°, the arc length is approximately 10.4720 cm.
Curves & bends
Arc Length Calculator
Solve any missing value in the arc-length relationship. Choose what you know, work in degrees or radians, and get a result without manually converting the angle.
FreeNo sign-inInstant results
INPUT
Choose the value to solve
Enter the other two measurements.
RESULT
Calculated instantly
Arc length10.472 cm
Radius10 cm
Central angle60°
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Straight answers
Common questions
Should I use degrees or radians?
Use the unit shown with your angle. The calculator converts degrees internally; the direct formula s = rθ expects θ in radians.
Can I find the angle from arc length?
Yes. Enter the radius and arc length, then choose central angle as the value to solve.
What is the difference between arc length and chord length?
Arc length follows the curved edge of a circle. Chord length is the straight-line distance between the same two endpoints.