/// Answer-first planning notes
How much concrete volume fits my entered footing geometry?
| Planning input | Calculation role | Field check |
|---|---|---|
| Footing quantity | Scales one footing volume | Count matching footing shapes only |
| Length, width, depth | Create net concrete volume | Use approved finished dimensions |
| Bag yield | Produces optional whole bags | Enter the selected product's stated yield |
Footing volume conversion uses the exact international foot while leaving structural design and product yield as explicit external inputs.
Evidence: National Institute of Standards and Technology/// Formula & field notes
How this concrete footing estimate works
FormulaNet volume = quantity × length × width × depth. Volume with waste = net volume × (1 + waste %). Bags = adjusted volume ÷ selected bag yield, rounded up.
Worked example
One 20 ft × 1.5 ft × 0.75 ft footing contains 22.5 ft³ (0.8333 yd³); with 10% waste and 0.60 ft³ per bag, order 42 bags.
/// Source trail
Data & assumptions
Every source has a declared scope. A reference can support a conversion or product assumption without turning this estimate into a supplier quote.
Exact international-foot to meter conversion; U.S. survey-foot conversion is explicitly outside this claim.
Effective 2025-08-18 · Reviewed 2026-07-15 · Next review 2027-07-15Independent confirmation that one international foot equals exactly 0.3048 meters; U.S. survey-foot conversion remains distinct.
Effective 2025-06-10 · Reviewed 2026-07-15 · Next review 2027-07-15/// Common questions
Concrete Footing calculator FAQ
What should I verify before ordering footing concrete?
Confirm field dimensions and approved footing dimensions and selected bag yield against the exact product or supplier information. ProjectQty shows the assumptions so you can replace planning defaults before ordering whole bags.
How does waste affect the footing concrete estimate?
Waste is applied after the base geometry is calculated and before discrete packages or pieces are rounded up. Use a higher allowance for complex layouts, cuts, pattern matching, breakage, or uncertain field dimensions.
Is this footing concrete result a professional design?
No. It is a quantity-planning result. This quantity tool cannot size a footing, determine soil bearing, select reinforcement, or establish structural or code compliance.