# Area of a 18 Inch Circle

What is the area of a circle with a

__of 18 inches (radius of 9 inches)? How big is a 18 inch circle?__**DIAMETER**Diameter

cm

Diameter

ft

in

Diameter

meters

Diameter

yards

Units

Area of a 18″ diameter circle

254.47 | square inches |

1.7671 | square feet |

0.19635 | square yards |

1,641.7 | square centimeters |

0.16417 | square meters |

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.