# Area of a 18 Centimeter Circle

What is the area of a circle with a DIAMETER of 18 cm (radius of 9 cm)? How big is a 18 centimeter circle?
Diameter
cm
Diameter
ft
in
Diameter
meters
Diameter
yards
Units
Area of a 18cm diameter circle
 254.47 square centimeters 0.025447 square meters 39.443 square inches 0.27391 square feet 0.030434 square yards
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.

Circle Area by Diameter
results may be rounded
Diameter cm2 in2 ft2
18.0 cm 254.5 39.44 0.2739
18.1 cm 257.3 39.88 0.2770
18.2 cm 260.2 40.32 0.2800
18.3 cm 263.0 40.77 0.2831
18.4 cm 265.9 41.22 0.2862
18.5 cm 268.8 41.66 0.2893
18.6 cm 271.7 42.12 0.2925
18.7 cm 274.6 42.57 0.2956
18.8 cm 277.6 43.03 0.2988
18.9 cm 280.6 43.49 0.3020