A natural hole is almost always an irregular shape, but you can calculate its approximate volume. A hole is a cylinder, so to find the volume of a hole, calculate the volume of a cylinder. The volume of a cylinder is defined as the number of cubic units that will fill that cylinder. This formula is pi * radius squared * height = volume. This can predict the volume of a post hole, a golf hole or a hole you're digging.
Measure the Radius
Measure the radius of the hole. To do this, measure the diameter, then divide by two. If the diameter of your hole is 6 centimeters, then the radius is 3 centimeters.
Measure the Height
Measure the height of the hole from top to bottom. This height also represents how deep the hole is. Assume that the height or depth for your hole is 10 centimeters.
Calculate the Volume
Plug your values into the formula that calculates the volume of a cylinder. This formula is pi * radius squared * height = volume. Pi is 3.142. The radius is 3. The height is 10. So, plug in your values of 3.142 * 3^2 * 10 and calculate. The volume is 282.78 cubic centimeters.