Area of a 21 Foot Circle
What is the area of a circle with a DIAMETER of 21 feet (radius of 10.5 feet)? How big is a 21 foot circle?
Diameter
cm
Diameter
ft
in
Diameter
meters
Diameter
yards
Units
Area of a 21′ diameter circle
| 346.36 | square feet |
| 49,876 | square inches |
| 38.485 | square yards |
| 0.0079513 | acres |
| 32.178 | square meters |
| 321,780 | square centimeters |
| 0.0032178 | hectares |
results may be rounded
Area of a Circle Formula
The area of a circle is pi times the square of its radius. The radius is half the diameter.
Area = π * (Diameter / 2)2
Diameter of a Circle
The diameter of a circle is the distance from one edge to the other, passing through the center. It is twice the radius.