Pad and isolated footing volume
Pad / Isolated Footing Concrete Calculator
Estimate concrete for one or more identical rectangular or square pad footings from the plan dimensions and depth you supply.
Pad-footing quantity
Enter the footing dimensions and count
For a square footing, enter the same value for length and width. Use separate calculations when footing sizes differ.
Enter dimensions, quantity, and a waste allowance, then calculate.
Methodology 1.0.0 · Calculator 1.0.0
How the pad-footing calculation works
Length × width × depth gives the raw volume for one rectangular pad; equal length and width represent a square pad. The calculator multiplies by the whole-number quantity, then applies the selected 0%, 5%, 10%, or 15% arithmetic waste allowance.
Verified example
Two 4 ft × 4 ft × 12 in square footings with 10% waste
1.30 yd³35.20 ft³
Independently derived case A totals 32 cubic feet before waste and 35.2 cubic feet, or about 1.30 cubic yards, after 10%.
Measurement tips
- For a square footing, enter the side length in both the length and width fields.
- Count only footings with identical plan dimensions and depth in one calculation.
- Exclude pedestals, piers, columns, grade beams, and slabs unless you intentionally include them and avoid counting the same concrete elsewhere.
- Use footing dimensions selected by applicable plans or a qualified professional; this calculator does not design the footing or evaluate soil.
Pad / Isolated Footing Concrete Formula Reference
Reviewed relationship
For dimensions supplied by the user, each pad footing is a rectangular prism:
volume per footing = footing length × footing width × footing depth
raw total = volume per footing × whole-number quantity
adjusted total = raw total × (1 + selected waste percentage)
A square footing is the same geometry with equal length and width. This single tool covers both shapes; there is intentionally no separate square-footing page.
Geometry and overlap convention
All footings in one calculation are assumed to have identical dimensions. Pedestals, piers, columns, grade beams, walls, and slabs are excluded. If two components meet, assign their shared concrete to one calculation only. Use separate calculations for different footing sizes.
Unit reference
The calculator uses the international definitions 1 foot = 0.3048 meter and 1 inch = 0.0254 meter. The NIST Guide to the SI, Appendix B documents the length and volume conversion factors. Source reviewed 2026-10-05.
Scope and limitations
- The user supplies footing length, width, depth, whole-number quantity, and a waste percentage.
- The waste choice is arithmetic only; 0% is the default and no allowance is recommended automatically.
- The calculator does not determine plan size, depth, reinforcement, column or pedestal design, bearing pressure, soil capacity, loads, settlement, or code compliance.
- Use dimensions from applicable plans or a qualified professional and verify ordering quantities for actual site conditions.