Math
Central Angle Calculator
Find a circle's central angle from arc length and radius.
Did this calculator solve your problem today?
✓ Thank you for your feedback!
Report issue to loopingon.com
Sponsored
The central angle subtends an arc at the centre of a circle.
The math behind it
In radians, the central angle equals arc length divided by radius. Multiply by 180/π for degrees.
Worked Example
Arc 7, radius 5 → 1.4 rad ≈ 80.2°.
Frequently Asked Questions
How is this related to arc length?
Arc length = radius × central angle (in radians).
Advertisement