Enter the radius (ft) and the depth of the core (ft) into the Calculator. The calculator will evaluate the Core Fill. 

Core Fill Formula

CF = pi*r^2 * D


  • CF is the Core Fill (ft^3)
  • r is the radius (ft)
  • D is the depth of the core (ft)

To calculate Core Fill, multiply the radius squared by pi times the depth.

How to Calculate Core Fill?

The following steps outline how to calculate the Core Fill.

  1. First, determine the radius (ft). 
  2. Next, determine the depth of the core (ft). 
  3. Next, gather the formula from above = CF = pi*r^2 * D.
  4. Finally, calculate the Core Fill.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

radius (ft) = 3

depth of core (ft) = 10


What is Core Fill and why is it important?

Core Fill refers to the volume of material (usually concrete, gravel, or sand) needed to fill the core or cavity of a structure, such as blocks in construction. It is crucial for ensuring the structural integrity and strength of the construction, providing support, and preventing collapse.

How do you measure the radius and depth accurately for Core Fill calculations?

To measure the radius and depth accurately, use a measuring tape or laser distance measurer. For cylindrical shapes, the radius is half the diameter, measured from the center to any point on the edge. Depth is measured from the top surface to the bottom of the core.

Can the Core Fill formula be used for shapes other than cylindrical?

The provided Core Fill formula (CF = pi*r^2 * D) is specifically for cylindrical shapes. For other shapes, such as rectangular cores, a different formula based on the shape’s volume calculation would be needed.

What types of materials can be used for Core Fill, and how do you choose?

Common materials for Core Fill include concrete, gravel, sand, or a mix of them. The choice depends on the construction requirements, cost, and the structural support needed. Concrete is preferred for its strength, while gravel and sand are used for drainage and cost-effectiveness.