Concrete Footing Calculator
Estimate concrete volume for a rectangular footing.
Footing Concrete Formula
Volume = length × width × depth × quantity.
How to Estimate Concrete Footing Volume
Footing calculations begin with the length, width and thickness of each footing. Convert all dimensions to compatible units, calculate the volume for one footing, then multiply by the number of footings. A small extra allowance can help cover spillage, uneven excavation and minor measurement differences.
Concrete Footing Example
A footing that is 8 ft long, 2 ft wide and 1 ft thick has a volume of 16 cubic feet before waste. Multiple identical footings can be totaled by multiplying that volume by the footing count.
What Affects the Final Quantity?
Irregular trench bottoms, over-excavation, stepped footings and field changes can increase the concrete required. Always check structural drawings before ordering material.
Frequently Asked Questions
Should footing dimensions come from plans?
Yes. Structural drawings and local code requirements should determine the actual footing size.
Do I need a waste allowance?
A modest allowance is commonly useful because excavations are rarely perfectly uniform.
Can I use this for strip footings?
Yes, provided you enter the correct total length, width and thickness.
Calculation Assumptions and Practical Limits
Footing concrete volume comes from footing length, width and thickness. Excavation irregularity, overpour, waste and required reinforcement do not appear in the pure geometric volume, and footing dimensions must follow soil, load and local code requirements.