Concrete & Masonry
Calculate continuous footing concrete separately from slabs or post holes so footing dimensions and repeated runs stay visible.
Change the defaults to match your project and the product you plan to buy.
Project result
See base volume, extra allowance, bulk cubic yards and 60/80 lb premix references for repeated rectangular footing runs.
Planning estimate only. Verify product coverage, package size, supplier specifications and project requirements before purchasing.
Methodology
length × width × depth
Width/depth converted to feet internally.
one-run volume × quantity
For equal rectangular footings only.
base volume × (1 + extra %)
Adds placement contingency.
ceil(volume ÷ bag yield)
Uses reference yields of 0.60 and 0.45 ft³.
Use footing dimensions from a qualified design, plan or applicable project requirement. Measure the total continuous run and keep different footing sizes as separate calculations. Width and depth should represent the concrete cross-section, not excavation size when formwork or soil conditions make the excavation larger.
The calculator provides volume and bag references only; it does not determine structural dimensions, reinforcement, bearing capacity or code compliance. Verify ready-mix minimums, premix bag yield and access before buying. For larger pours, compare the calculated cubic yards with supplier delivery practices instead of defaulting to bagged concrete.
Reference
| Planning item | Starting point | Verify / adjust |
|---|---|---|
| Footing size | Use design dimensions | Calculator does not size structural footings. |
| Volume | L × W × D | Keep unlike runs separate. |
| Extra | Placement contingency | Choose for project conditions. |
| Premix yield | Check product label | Reference yields vary. |
Questions
No. It calculates quantity from dimensions you provide; structural footing design must be determined separately.
Yes with the quantity input. Calculate different sizes separately.
Use the actual concrete cross-section, which may differ from excavation dimensions depending on the construction method.
Planning guides
Concrete
Calculate continuous footing volume from run length, concrete width and concrete depth, while keeping design requirements separate from quantity math.
Read guide →Estimate concrete volume in cubic yards plus common premix bag quantities for slabs and pads.
Open calculator → Concrete & MasonryEstimate concrete volume and premix bags for cylindrical post holes after subtracting the post volume.
Open calculator → Concrete & MasonryEstimate concrete for round columns or piers from diameter, height, quantity and extra allowance, with cubic yards and bag references.
Open calculator →