Gravel Calculator
Estimate gravel or aggregate needed to cover a driveway, path, or base course by area and depth.
Estimates are for planning purposes only. Actual quantities depend on gravel type, moisture content, and compaction method. Verify quantities with your supplier before ordering.
How it works
- 1Enter the length and width of the area in metres or feet.
- 2Set the depth in centimetres or inches (10 cm / 4 in is typical for a driveway base course).
- 3The calculator multiplies area × depth for the volume, then applies a gravel bulk density of 1680 kg/m³ to give the mass to order.
Use cases
- Estimating gravel for a residential driveway or parking area.
- Calculating aggregate for a garden path or patio sub-base.
- Sizing a road base or compacted gravel layer for construction projects.
Frequently asked questions
How is the gravel volume calculated?
Volume = length × width × depth. A 6 m × 3 m area at 10 cm (0.10 m) deep gives 6 × 3 × 0.10 = 1.8 m³. At about 1680 kg/m³ that is roughly 3.0 tonnes.
Why should I add about 20% extra?
Loose gravel compacts when rolled or driven over, reducing the final depth by roughly 15–25%. Ordering about 20% more ensures you reach the target depth after compaction without a second delivery.
Does gravel density vary?
Yes. This calculator uses 1680 kg/m³, a common figure for medium crushed stone and pea gravel. Fine gravel can be nearer 1500 kg/m³ and dense limestone up to 1900 kg/m³. Confirm with your supplier for a precise order.
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