Gravel Calculator
Calculate gravel volume, US tons, metric tonnes and material cost from area and depth. Compare prices per ton or cubic yard using your supplier’s density.
How much gravel do I need?
Measure the area and the depth you want to fill. For a rectangle, multiply length by width. For a circle, multiply π by the square of half the diameter.
Weight (kg) = volume (m³) × bulk density (kg/m³)
A 20 ft × 10 ft area at 3 inches deep needs 50 cubic feet, or about 1.85 cubic yards. At the example density of 1,600 kg/m³, that is about 2.27 metric tonnes or 2.50 US short tons. Adding 10% extra brings the volume to about 2.04 cubic yards.
Gravel coverage per ton
Coverage depends on depth and bulk density. At the example 1,600 kg/m³ density, one metric tonne occupies 0.625 m³ and covers about 8.20 m² at 7.62 cm deep. A US short ton is lighter and covers less at the same depth. For the volume alone, use the cubic yard calculator.
Pea gravel and crushed stone: use the right density
The same cubic yard can weigh different amounts. At 1,600 kg/m³ it weighs about 1.2233 metric tonnes; at 1,800 kg/m³ it weighs about 1.3762 tonnes. These are comparison values, not fixed densities for either product. Bulk density includes the spaces between stones; solid-rock density is not a substitute. Ask your supplier for the value for the gravel you intend to buy.
Estimate gravel cost per ton or cubic yard
Match the price unit to your quote. At an example bulk density of 1,600 kg/m³, one cubic yard weighs about 1.2233 metric tonnes. A quote of $50 per metric tonne therefore gives a material cost of $61.16 per cubic yard, before allowance, tax or delivery.
A US short ton is a different unit, so choose it only when the supplier quotes that basis. For the calculation behind the weight estimate, see how to convert cubic yards to tons.
Depth is the layer thickness used in this geometric estimate. Compaction changes how much loose material is needed. Ask your supplier whether its density and recommended allowance describe loose or compacted gravel.
Unit reference: NIST volume conversion factors.
Common questions
Is a ton the same as a tonne?
A US short ton is 2,000 pounds, or 907.18474 kg. A metric tonne is 1,000 kg. This calculator labels them separately; confirm which unit is on your quote.
Why do suppliers give different gravel weights?
Bulk density varies with stone type, particle size, voids and moisture. The default density is only an example, so replace it with the value for your material.
Does extra material account for compaction?
It adds the percentage you enter to the calculated volume. No automatic compaction factor is applied. Use an allowance appropriate to the specified material and installation.
Questions about a result? See how our calculators are built or report a calculation issue.