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Linked base · Last reviewed 2026-07-12

Gravel base calculator with visible compaction and density

Estimate the material needed for a rectangular base or reuse a slab's measured length and width. The result separates finished compacted volume from loose purchase volume before converting it to estimated short tons.

Choose a gravel source

Nothing is saved until a valid temporary calculation is added to a project.

Compaction, waste, and density remain visible and editable because aggregate behavior varies by material, moisture, grading, and supplier.

Compacted volume, loose volume, and weight

Purchase yd³ = compacted ft³ × loose factor × (1 + waste%) ÷ 27; tons = purchase yd³ × density

Compacted ft³ is length times width times compacted depth. A factor of 1.10 means acquire 1.10 loose units for each 1.00 desired compacted unit; it is not a hidden shrinkage percentage.

Density converts the final purchase volume to estimated short tons. When zones use different densities, the project keeps separate labeled weight groups instead of silently adding incompatible tonnage.

Worked example: gravel under the same patio footprint

A 10 ft × 12 ft footprint with a 4 in compacted base contains 40.00 ft³ compacted. At a 1.10 loose-to-compacted factor, loose volume is 44.00 ft³ and the compaction allowance is 4.00 ft³.

Adding 5% waste gives 46.20 ft³, or 1.71 yd³, to purchase. At the editable density of 1.40 short tons per yd³, estimated weight is 2.40 short tons. These values match normative Fixture B.

Generic presets that you can replace

The starting loose-to-compacted factor is 1.10, gravel waste is 5%, and density is 1.40 short tons per yd³. These are generic planning presets reviewed July 11, 2026, not facts about every aggregate.

Enter compacted depth from your own plan. Replace density or compaction information with material- and supplier-specific values when available.

Measure once when the base follows a slab

Enable linked gravel from a valid slab to reuse length and width. Enter an independent compacted depth, then review compacted, loose, waste-adjusted, yard, and ton results in order.

Aggregate quantity boundary

This rectangular quantity estimate does not recommend an aggregate, compacted depth, compactor, drainage design, or subgrade preparation. It does not correct for moisture, slope, frost, bearing, field loss, or supplier conversion rules.

Concrete and gravel remain separate materials. Gravel tons are estimates derived from the density you selected and must be confirmed before ordering.

Sources and review dates