`A = pi*(( "R" )^2 - ( "r" )^2)`

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The Area of Circular Annulus calculator computes the are of an annulus (ring)

INSTRUCTIONS: Choose units and enter the following:

• (R) Radius of Outer Circle
• (r) Radius of Inner Circle

Area of Circular Annulus (A): The area is returned in square meters.  However, these can be automatically converted to compatible units via the pull-down menu.

The Math / Science

(Annulus) This formula provides the area of an annulus given the inner (r) and outer (R) radii.

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