Curved Surface Area of a Cone

To find the curved surface area of any cone, multiply the base radius of the cone by pi.  Now multiply your answer by the length of the side of the cone.  If you want to total surface area remember to add on the area of the base of the cone.  Try the interactive example below.  Answers are rounded to two decimal places.

Radius (r) =        Length (l) =



Curved Surface Area = πrl

Total Surface Area = πrl + πr2

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