Driveway Gravel Calculator

Building or resurfacing a gravel driveway? This driveway gravel calculator estimates cubic metres and tonnes for a compacted driveway build, with 20mm blue metal preselected — the standard crushed aggregate for Australian driveways. Plan on a 100 mm compacted depth over a prepared base.

Driveway Gravel Calculator

How much gravel do you need? Enter your area below – results in cubic metres & tonnes.

Length (m)

Width (m)

Depth (m)

Gravel type Add 10% extra for compaction & wastage (recommended)

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

How to use the calculator

Measure your driveway length and width in metres, and enter 0.1 m for a 100 mm compacted layer.
Keep 20mm Blue Metal selected — it compacts firmly and handles vehicle traffic.
Leave the 10% extra box ticked to allow for compaction and uneven subgrade, then press Calculate.

FAQs

How thick should a gravel driveway be?

A 100 mm compacted layer of 20mm aggregate over a firm, well-drained subgrade suits most residential driveways. Soft or clay soils may need a thicker base layer of crushed rock underneath.

What is the best gravel for an Australian driveway?

20mm blue metal (crushed aggregate) is the go-to choice: its angular particles lock together when compacted, giving a firm surface that resists rutting. Rounded stones like pea gravel shift under tyres and are best avoided.

How do I prepare the base for a gravel driveway?

Strip organic topsoil, shape the subgrade with a slight crown or crossfall for drainage, and compact it firmly. Lay the aggregate in layers, watering lightly and compacting each layer before adding the next.