How to Calculate the Volume of a Cone

Step-by-Step Guide

1. 1

   Step 1: Find the radius.

   If you already know the radius, then you can move on to the next step.
   
   If you know the diameter, divide it by 2 to get the radius.
   
   If you know the circumference, divide it by 2π to get the diameter.
   
   And if you don't know any of the measurements of the shape, just use a ruler to measure the widest pie circular base (the diameter) and divide that number by 2 to get the radius.
   
   Let's say the radius of this cone's circular base is .5 inches (1.3 cm). , To find the area of the base circle, you can just use the same formula you'd use to find the area of a circle:
   A = πr2.
   
   Plug ".5" in for r to get A = π(.5)2 and square the radius and multiply it by the value of π to find the area of the circular base. π(.5)2 = .79 in.2. , If you know it already, write it down.
   
   If you don't know it, use a ruler to measure it.
   
   Let's say the height of the cone is
   1.5 inches (1.3 cm).
   
   Make sure that the height of the cone is written in the same measurements as the radius. , Multiply the area of the base, .79 in.2, by the height,
   1.5 in.
   
   So, .79 in.2 x
   1.5 in =
   1.19 in.3 , Simply divide
   1.19 in.3 by 3 to find the volume of a cone.
   1.19 in.3/3 = .40 in.3.
   
   Always state the volume in cubic units because it's a measure of three-dimensional space.
2. 2

   Step 2: Use the radius to find the area of the base circle.

3. 3

   Step 3: Find the height of the cone.

4. 4

   Step 4: Multiply the area of the base by the height of the cone.

5. 5

   Step 5: Divide the product by three.

Detailed Guide

About the Author