Pile Cap Calculator — ft, yd³, rebar
How to use this calculator
A pile cap is a thick reinforced concrete block that sits on top of a group of piles to distribute column loads. Enter the cap shape, number of caps, dimensions, depth, and number of piles per cap. The SVG shows plan view with pile positions and a cross section.
Cost — pick ready-mix per yd³, 80-lb bags, or 60-lb bags.
Reinforcement — bottom mat with bars in both directions per ACI 318-19, 3″ cover over piles.
Labor — rate per cap, per yd³, or flat price.
Saved Calculations
| Time | Caps | Size | Piles | Vol yd³ | Cost | Rebar | Labor | Total |
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How to Calculate Concrete for Pile Caps
A pile cap is a thick reinforced concrete block placed on top of a group of piles (driven or drilled) to transfer and distribute structural loads. This calculator estimates concrete volume in cubic yards, number of bags, weight, bottom rebar mat, and cost for square or rectangular pile caps with 2, 3, 4, 6, or 9 pile configurations.
Reinforcement per ACI 318-19
Pile caps require a bottom reinforcement mat in both directions, placed with 3″ clear cover above the pile tops. Typical bar sizes are #5 to #6 at 6–12″ on center. The calculator accounts for lap splices and cutting waste.
Formulas
Volume = Width × Length × Depth × Number of caps × (1 + Waste%). Weight ≈ Volume × 4,050 lbs/yd³. Rebar: bars per direction = span / spacing + 1, in both directions.
