Gravel Base Calculator
Calculate the finished compacted volume for a rectangular base. Enter your supplier’s bulk density if you want a rough weight estimate.
How the calculation works
Compacted cubic feet = length × width × (depth in inches ÷ 12). Divide by 27 for cubic yards. Additional material = compacted volume × (1 + allowance ÷ 100). Optional short tons = adjusted cubic feet × supplied bulk density in lb/ft³ ÷ 2,000.
Worked example
A 20 × 10 ft base at 4 in compacted depth has 66.67 ft³, or 2.47 yd³. At 10% additional material, plan for about 2.72 yd³ before supplier rounding.
Before you order
The extra percentage is a planning allowance, not a guaranteed compaction ratio. Loose-to-compacted volume depends on aggregate, moisture and method. Ask the supplier for density and delivery increments.
Review the calculation method and source notes, then use the supplier checklist before placing an order.
Continue planning
Content and calculator by pourmeasure. Formula and assumption notes: methodology and sources. Updated October 2026. No independent engineering review is claimed.