Sector Area Calculator
Find the area of a sector (a pie slice) from the central angle and the radius or diameter.
Change the values and press Calculate to work out your own figures.
Enter the central angle and either the radius or the diameter.
| Amount | Unit |
|---|---|
| 0.005235987756 | m² |
| 52.35987756 | cm² |
| 0.05635970315 | ft² |
| 8.115797253 | in² |
| 0.006262189239 | yd² |
| 1.293840752e-6 | acres |
Show the working
- θ = 60°
- Sector area = ½ r² θ (θ in radians) = θ/360 × π r²
- Arc length = r θ
- Sector area = 52.35987756 cm²
How to use it
Enter the central angle and either the radius or the diameter.
Enter the measurements (decimals, fractions such as 3/4, or mixed numbers such as 1 1/2) and, if you like, their unit; the answer is then also given in other units. Show the working gives the formula.
Key facts
A = θ/360 × π r² = ½ r² θ (radians)
A slice of pie
A 60° slice is one sixth of the whole circle's area.
Questions
What is the area of a 60° sector of radius 10?
50π/3 ≈ 52.35987756.
What about 360°?
The whole circle, π r².
Formulas
A = θ/360 × π r² = ½ r² θ (radians)
Sources
Limitations
- All measurements in one calculation use the same unit; the answer is also given in other units.
- Measurements up to 10¹⁵.