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?
ft
in
Area of a 21′ diameter circle
346.36square feet
49,876square inches
38.485square yards
0.0079513acres
32.178square meters
321,780square centimeters
0.0032178hectares
(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.

Diameter
Circle Area by Diameter
(results are rounded)
Diameter ft2 in2 m2
21′0″ 346.4 49,876 32.18
21′1″ 349.1 50,273 32.43
21′2″ 351.9 50,671 32.69
21′3″ 354.7 51,071 32.95
21′4″ 357.4 51,472 33.21
21′5″ 360.2 51,875 33.47
Diameter ft2 in2 m2
21′6″ 363.1 52,279 33.73
21′7″ 365.9 52,685 33.99
21′8″ 368.7 53,093 34.25
21′9″ 371.5 53,502 34.52
21′10″ 374.4 53,913 34.78
21′11″ 377.3 54,325 35.05