Concrete & Masonry

Concrete Footing Calculator

Estimate volume and optional 80 lb bag equivalents for rectangular footings using length, width, depth, quantity, and waste allowance.

Project measurements

Measurement system

This calculator measures entered rectangular footings only. It does not recommend footing size or interpret building codes.

How to use this calculator

  1. Choose a measurement system.
  2. Enter the rectangular length, width, and depth of one footing.
  3. Enter the number of identical footings.
  4. Add waste and calculate the total volume.

How the calculation works

One footing’s rectangular volume is multiplied by the footing count. Waste is then applied to the combined volume, which is converted to cubic yards and cubic meters.

Formula

One footing = length × width × depth
Base volume = one footing × quantity
Adjusted volume = base volume × (1 + waste % ÷ 100)

Worked example

Three footings measuring 10 ft × 2 ft × 1 ft contain 60 cubic feet. With 5% waste, the estimate is 63 cubic feet, or about 2.33 cubic yards.

Project considerations

  • This calculator measures entered geometry only.
  • It does not determine footing dimensions, reinforcement, bearing capacity, or code compliance.
  • Measure each differently sized footing as a separate calculation.

Frequently asked questions

Does this calculator size a footing?

No. Enter dimensions established for the project; the result is volume only.

Are round piers included?

No. This tool is specifically for identical rectangular footings.