Circle Sector Perimeter Table: Sector perimeter by Radius
Reference table of sector perimeter for Circle Sector Perimeter across a range of radius values — exact, engine-computed figures you can read off at a glance.
Circle Sector Perimeter Calculator
Verified formula Updated Jun 2026 Private — runs on your device
Verified formula
Private
Sector perimeter
17.8540
- Arc length
- 7.8540
For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.
How to use the Circle Sector Perimeter Calculator
The Circle Sector Perimeter Calculator works out your sector perimeter, along with 1 related figure in an instant. Enter radius and central angle and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.
- Enter the radius.
- Enter the central angle.
- Read off your sector perimeter, together with arc length — the calculator updates automatically, with no button to press.
Formula
The Circle Sector Perimeter Calculator uses the formula:
Sector perimeter = Radius × Central angle × 3.141592653589793 ÷ 180 + 2 × Radius
Worked example
For example, with radius of 5 and central angle of 90 degrees, the sector perimeter is 17.8540.
| Radius | 5 |
|---|---|
| Central angle | 90 degrees |
| Sector perimeter | 17.8540 |
|---|---|
| Arc length | 7.8540 |
Results are estimates for educational use, not professional advice.
Key terms explained
- Perimeter
- The total distance around the outside of a two-dimensional shape.
- Radius
- The distance from the centre of a circle or sphere to its edge.
Frequently asked questions
Add the arc length to two radii. A radius of 5 and a 90-degree angle give a perimeter of about 17.85.
Arc = radius × angle in radians, which is radius × angle × π ÷ 180 when the angle is in degrees.
A sector is bounded by two straight radii and the curved arc, so all three are added.
The arc becomes the full circumference, and the two radii overlap, so it is effectively the whole circle.
The Circle Sector Perimeter Calculator uses the formula: Sector perimeter = Radius × Central angle × 3.141592653589793 ÷ 180 + 2 × Radius. For example, with radius of 5 and central angle of 90 degrees, the sector perimeter is 17.8540.
Enter the radius. Enter the central angle. Read off your sector perimeter, together with arc length — the calculator updates automatically, with no button to press.
Related guides
How to Calculate Circle Sector Perimeter: Formula, Steps & Examples
Learn how to calculate Circle Sector Perimeter — the formula explained step by step, with worked examples and a free calculator to check your answer.