# Area of a 40 Inch Circle

What is the area of a circle with a

__of 40 inches (radius of 20 inches)? How big is a 40 inch circle?__**DIAMETER**Diameter

cm

Diameter

ft

in

Diameter

meters

Diameter

yards

Units

Area of a 40″ diameter circle

1,256.6 | square inches |

8.7266 | square feet |

0.96963 | square yards |

8,107.3 | square centimeters |

0.81073 | 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.