Estimate strip footing material
Concrete Footing Calculator
Use this concrete footing calculator to figure concrete for a continuous strip footing or trench. Enter the total run, width, and depth from your plans; add separate runs as additional pours or use the quantity field for identical sections.
Footing estimate
Measurement system: Imperial. Planning estimate based on the dimensions and allowance shown below.
Build your estimate
Choose a shape, enter measured dimensions, then review every step.
Enter the dimensions of the concrete itself. This estimate does not subtract posts or wall openings.
Bag yields and product settings
Yield differs by product. These common examples are editable.
Bag counts are rounded up. The 40, 50, 60, and 80 lb rows show common US products; use the package yield for your product.
Optional: price your materials
Enter local prices. No regional or supplier price is assumed.
Material estimate only. Delivery, taxes, labor, and supplier minimums are not included.
Calculation and assumptions
Rectangular strip footing volume
Worked example: 24 ft run × 18 in wide × 6 in deep
- Convert 18 in to 1.5 ft and 6 in to 0.5 ft.
- Net volume = 24 × 1.5 × 0.5 = 18 ft³, or 0.67 yd³.
- With a chosen 10% allowance, plan for 19.8 ft³, or 0.73 yd³.
Use dimensions from the approved plan
- This tool estimates material quantity; it does not size a footing or trench.
- For multiple shapes or stepped sections, calculate each rectangular section separately and add the volumes.
- It does not account for reinforcement, soil, displaced forms, intersecting runs, or local ordering increments.
All example quantities are geometry and arithmetic illustrations. Confirm measurements, product yields, ordering rules, and project requirements with your plans and supplier.