Gravel Tonnage Calculator

Australian landscape suppliers sell gravel by the tonne, but your project is measured in metres. This calculator converts your length, width and depth into cubic metres, then into tonnes using typical Australian bulk densities — so you order the right amount the first time.

How to use

  • Measure your area in metres and enter the length, width and depth (100mm = 0.1m).
  • Choose your gravel type so the correct bulk density is applied.
  • Keep the 10% extra ticked for compaction and wastage, then press Calculate.

Gravel Tonnage Calculator

How much gravel do you need? Enter your area below — results in cubic metres & tonnes.
Please enter valid numbers for length, width and depth.
Volume needed
Weight
20kg bags (approx.)
Estimates use typical bulk densities shown above. Actual density varies by supplier and moisture — confirm with your landscape supplier before ordering. How our calculators work

Related calculators: Gravel Calculator, Blue Metal Calculator, Topsoil Calculator

Frequently asked questions

How many tonnes of gravel do I need for a driveway?

A 20m × 3m driveway at 100mm deep is 6m³. With 20mm blue metal (1.6 t/m³) that is about 9.6 tonnes, or roughly 10.6 tonnes with 10% extra.

How many cubic metres are in a tonne of gravel?

Divide 1 by the bulk density: one tonne of 20mm blue metal (1.6 t/m³) is about 0.63m³, and one tonne of crusher dust (1.8 t/m³) is about 0.56m³.

Should I order extra gravel?

Yes — allow 10% for compaction, spillage and uneven ground. It is cheaper than paying a second delivery fee.