Perimeter of a Segment Calculator

Summary

Calculate the perimeter of a circular segment — arc length plus chord length — from radius and central angle.

How it works

1. Enter the radius of the circle.
2. Enter the central angle in degrees or radians.
3. The calculator converts degrees to radians if needed.
4. Arc length is computed as r × θ (radius times angle in radians).
5. Chord length is computed as 2r × sin(θ / 2).
6. The perimeter is arc length + chord length.

Use cases

• Engineering designs involving curved cuts or arched panels.
• Architecture — calculating material needed for arched window frames.
• Woodworking and metalworking templates with circular cutouts.
• Geometry homework and exam preparation.
• Surveying land parcels bounded by arc sections.
• Manufacturing gaskets or seals with circular segment shapes.

Frequently Asked Questions