Area of a Circular Ring - Geometry Calculator

Online calculator to calculate the enclosed area (in blue) of a circular ring when outer and inner radii are known.

formula for area of circular ring

Figure 1. Formula for area of circular ring

How to use the calculator

Enter the outer and inner radii R1 and R2 (with R1 > R2) as positive real numbers and press "enter". The output is the area of the circular ring.

R1 =
R2 =
area =

More References and links

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