One cubic yard of gravel has no universal weight because mass equals volume multiplied by the named material’s bulk density. A 1.0 yd³ load at 1.35 tons/yd³ weighs 1.35 tons, while 1.0 yd³ at 1.55 tons/yd³ weighs 1.55 tons. Stone type, voids, moisture, and loose or compacted condition change the conversion.
Worked example with numbers
A path is 6.0 m long, 2.0 m wide, and 0.08 m deep. Its loose placement volume is 6.0 × 2.0 × 0.08 = 0.96 m³. If a supplier states 1,600 kg/m³ for the named loose aggregate, the mass estimate is 0.96 × 1,600 = 1,536 kg, or 1.536 metric tonnes. Replacing the density with a guessed “one yard equals one ton” changes the result without changing the measured path.
How to make the calculation
Calculate volume first, then ask the supplier for the density and sales unit of the exact aggregate: crushed stone, pea gravel, drainage rock, or another named grade. Ask whether the value is loose, compacted, dry, or wet. Enter that stated density in the gravel calculator; its default is an example input, not a specification for every quarry.
Check the units and assumptions
Bulk density is mass divided by the bulk volume, including air spaces between pieces. It differs from the density of the rock particles themselves. A tonne is a mass unit and a cubic yard is a volume unit, so no direct conversion exists until bulk density is supplied. Record kg/m³ or tons/yd³ with the estimate, not merely a bare number.
Common mistakes
Do not use a density for dry sand to estimate wet gravel. Do not mix short tons, metric tonnes, and long tons without spelling out the unit. Do not convert a compacted design volume to a loose delivery volume without a supplier-approved compaction factor. Another error is using bed area in square metres as though it were cubic metres and forgetting depth.
When this result does not apply
This is a planning estimate for material quantity. It does not establish drainage performance, bearing capacity, gradation, compaction method, truck payload, access, or structural suitability. A driveway, retaining-wall base, or engineered drainage system needs the relevant design and local requirements, not an assumed aggregate weight.
Source for the external fact
The U.S. Geological Survey describes bulk density as weight divided by volume and notes that packing force affects it in its bulk-density methods. That source directly explains why a volume-to-mass factor depends on material condition.
Related calculators
Find the bed volume with the gravel quantity calculator, compare a bark bed in the mulch estimator, and calculate a solid pour separately with the concrete-volume tool.