Foundation Material Estimator
Concrete Footing Calculator
Estimate concrete for continuous wall footings, garage footings, shed footings, and deck beam footings. Enter run length, width, depth, and number of runs to get cubic yards, bags, waste, and material cost.
Enter Footing Dimensions
Save this estimate or download a PDF report
The PDF report uses the current calculated result. Save the estimate first when you want to reuse the inputs later.
Results
Live estimateQuick answer
A 40 ft continuous footing that is 16 in wide and 8 in deep needs about 1.45 yd3 with 10% waste, or about 66 80 lb bags. For garage, wall, shed, or deck beam footings, calculate each run by length, width, and depth before comparing bags with ready-mix delivery.
Footing inspection scope
Turn footing yards into a quote and inspection checklist
Recent footing calculators answer trench volume. A footing that is ready to buy also needs the next checks: actual trench condition, frost depth, rebar, forms, inspection hold points, and concrete placement access.
Scope status
Structural quote check
67/100 scope-readiness score
Run length
20 ft total
16 in wide x 8 in deep
Buying pressure
Bag-friendly small footing
33 bags / 0.7243 yd3
| Scope item | Status | What to verify |
|---|---|---|
| Actual trench dimensions | confirm | Waste is at least 10%, but measure trench width and depth after excavation. |
| Frost depth and bearing surface | ask | Confirm local footing depth, undisturbed bearing material, and inspection requirements before the pour. |
| Rebar, dowels, and laps | ask | Material volume does not design reinforcement; written quotes should separate bar size, chairs, dowels, and laps. |
| Forms and excavation scope | confirm | Clarify who handles excavation, bottom cleanup, forms, bracing, spoils, and backfill readiness. |
| Truck, chute, pump, or buggy access | confirm | Footings often sit away from the truck; ask whether chute reach, pump, buggy, wheelbarrow, or wait-time fees apply. |
| Inspection and pour hold point | ask | Confirm whether the trench and rebar need approval before concrete arrives, and who pays if the pour is delayed. |
Formula
One footing run
Volume per run = length x width x depthVolume per run = 20 x 1.333 x 0.667All runs
Raw volume = volume per run x runsRaw volume = 17.7778 before wasteWaste and bags
Final volume = 17.7778 x (1 + 10%/100)Bags = ceil(final volume / 0.6)Example Footing Estimates
Footing Size Notes
| Topic | Note |
|---|---|
| Footing width | Depends on load, soil bearing capacity, wall thickness, and local code. |
| Footing depth | May need to reach below frost depth or suitable bearing material. |
| Reinforcement | Rebar size and placement are design details, not material volume assumptions. |
| Trench condition | Uneven excavation can increase concrete volume beyond the clean rectangle. |
Before You Pour
- Measure the actual trench dimensions after excavation.
- Calculate different footing sizes separately, then add them.
- Keep over-excavation, loose sidewalls, and bottom irregularity in mind.
- Confirm inspection, reinforcement, and local code requirements before scheduling concrete.
Footing Buying Guide
Use the calculator for the material quantity, then use the written guide to check the quote details that can change the installed price: actual trench width and depth, rebar, dowels, inspection timing, chute reach, pump or buggy needs, cleanup, permits, and labor.
Open the concrete footing calculator guide before treating the cubic-yard result as a full project budget. For worked examples, compare the concrete footing calculation examples. If the project uses round holes instead of continuous runs, switch to the concrete post hole calculator.
Frequently Asked Questions
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Disclaimer: This calculator estimates concrete material volume only. It does not design footing size, bearing capacity, reinforcement, frost protection, drainage, or code compliance. Consult a qualified contractor, engineer, or local building department for structural footing requirements.