Perimeter of a Sector Calculator
Enter a radius and central angle to instantly get the perimeter (arc length + two radii) of a circular sector.
Sector Inputs
Any positive unit (cm, m, in, …)
Results
Enter values and click Calculate
Arc Length
r × θ (in radians)
Two Radii
2 × r
Total Perimeter
Arc length + 2r
Angle Used
Formula Reference
Arc Length
L = r × θ
θ in radians
Two Radii
= 2r
straight edges
Perimeter
P = 2r + rθ
= r(2 + θ)
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Summary
Enter a radius and central angle to instantly get the perimeter (arc length + two radii) of a circular sector.
How it works
- Enter the radius of the circle.
- Enter the central angle and choose degrees or radians.
- The calculator converts the angle to radians if needed.
- Arc length is computed as r × θ (radians).
- Perimeter is returned as arc length + 2 × radius.
Use cases
- Calculate material length for a fan-shaped garden bed.
- Determine the border trim needed for a pie-slice floor tile.
- Solve geometry homework involving circular sectors.
- Verify arc-length answers from engineering drawings.
- Estimate fencing for a curved agricultural plot.
- Check pie-chart segment boundaries in data-visualization work.
Frequently Asked Questions
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Last updated: 2026-05-23 ·
Reviewed by Nham Vu