Arc Length calculator.
Solve a circular arc from radius and angle, radius and arc length, or angle and arc length.
Your inputs
Schematic only. Use your measured dimensions and the stated angle convention.
Use measurements from your plan and properties from your chosen product. Any prefilled values are illustrative.
A clear estimate starts here.
Enter your dimensions and product details to see the quantity and purchase breakdown.
Formula and assumptions
How this calculation works.
Choose the pair of supplied arc measurements. Arc angle is at most one full circle. The tool also returns radius, chord, segment rise and sector area. A measured chord and rise belong to the separate Radius from Chord and Rise tool.
A worked example
Illustrative inputs only. Product properties and design dimensions are not recommendations for your project.
- Known measurements
- Radius and angle
- Radius
- 2 m
- Centre angle
- 90 °
Arc length: 3.14 m
Before you purchase
Use dimensions from your plan and properties from your chosen product. Any design spacing, section or fixing pattern must already be specified.
Method: dimensional arithmetic and user-supplied specifications. Software checks: 2026-10-04. Calculation and review policy.