From measured space to purchasable material
Footing takeoffs often combine a continuous strip under a wall with separate pads under posts. This calculator keeps those two quantities visible so you can compare them with a drawing or supplier quote. Enter the total measured strip length, its specified cross section, and the number and dimensions of any square pads. A combined allowance is applied after both volumes have been calculated. The tool does not establish bearing capacity, footing size or reinforcement and should be used only after those requirements have been determined.
Measure, select yield and round the order
- Add the lengths of continuous footing runs.
- Enter the specified strip width and depth.
- Add individual pads and review the combined cubic-yard order.
Net requirement and purchase calculation
A worked example
An 80 ft strip, 20 in wide and 10 in deep, uses 111.11 ft³. Four 24 × 24 × 12 in pads add 16 ft³, producing 5.18 yd³ with 10% allowance.
Concrete Footing: what changes the result?
Compare dimensions and product yields without treating quantities as a design check. The comparisons below are calculated from this page’s default example. Each row changes only the named input; all other inputs stay at their displayed example values. These are mathematical scenarios, not measurements from a completed project.
| Changed assumption | Default input | Comparison input | Result: default → comparison |
|---|---|---|---|
| Total strip footing length | 80 ft | 96 ft | Strip footing volume: 111.1111 → 133.3333 cu ft Combined footing volume: 127.1111 → 149.3333 cu ft |
| Strip width | 20 in | 24 in | Strip footing volume: 111.1111 → 133.3333 cu ft Combined footing volume: 127.1111 → 149.3333 cu ft |
| Strip depth | 10 in | 12 in | Strip footing volume: 111.1111 → 133.3333 cu ft Combined footing volume: 127.1111 → 149.3333 cu ft |
| Number of square pads | 4 | 5 | Pad footing volume: 16 → 20 cu ft Combined footing volume: 127.1111 → 131.1111 cu ft |
Displayed values are rounded. Whole-pack results change in steps; continuous quantities may change before a new pack is needed. To compare your actual project, enter your dimensions above, save a scenario, then change one assumption.
Coverage, allowance and purchasing limits
- Measure intersections carefully; overlapping strips can cause double counting.
- This tool assumes straight-sided forms rather than irregular excavations.
- Do not choose footing dimensions solely to match a concrete order size.
Frequently asked questions
Does a footing calculator determine the correct footing size?
No. Soil conditions, building loads and local requirements determine footing design.
How do I estimate several identical pad footings?
Enter the count plus the side length and depth of one square pad.
Should trench overbreak be included?
If concrete is placed against soil, compare actual excavation dimensions with the specified form dimensions and adjust the takeoff appropriately.
Calculation method: JICWH methodology. Examples are planning assumptions, not product recommendations.