🏛️Concrete Footing Calculator
Get cubic yards and bags of concrete for continuous or pad footings.
Your footings
You'll need about
2.26 cubic yards
102 bags of 80 lb or 136 bags of 60 lb (incl. 10% waste)
cubic yards
2.26
cubic feet
61.1
80 lb bags
102
60 lb bags
136
🛒 Shopping list
- Concrete mix (80 lb bags)102 bags
- …or ready-mix delivery2.50 cubic yards
Footings must go below your local frost line and sit on undisturbed soil — check local code for size and depth.
How it works
Continuous footing volume = length × width × depth. Pad footings = count × size² × depth. Add waste, divide cubic feet by 27 for cubic yards. Bags: an 80 lb bag makes about 0.6 cu ft, a 60 lb bag about 0.45 cu ft.
Worked example
A 40 ft continuous footing, 20 in wide and 10 in deep = 55.6 cu ft. With 10% waste that's 61.1 cu ft = 2.26 cubic yards, or 102 bags of 80 lb (136 of 60 lb).
Questions people ask
Below your frost line, and per local code.
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Last updated October 8, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.