Gravel Driveway Material Calculator
Estimate the gravel needed for a driveway from length, width and planned depth, then convert the quantity to tonnes, truck loads and material cost.
Driveway inputs
Driveway gravel requirement
How driveway gravel quantity is calculated
The basic quantity is the driveway area multiplied by the selected aggregate depth. An explicit allowance is then applied before converting the volume to tonnes.
Base volume = area × depth ÷ 1,000
Planning volume = base volume × (1 + allowance)
Tonnes = planning volume × bulk density
Truck loads = ceiling(tonnes ÷ truck capacity)
Worked example
A 35 × 4 m driveway has 140 m² area. At 150 mm depth, the geometric aggregate volume is 21 m³. With an 8% allowance it becomes 22.68 m³. At 1.65 t/m³, the planning quantity is about 37.42 tonnes.
Why depth is the strongest driver
Increasing a layer from 100 mm to 150 mm increases that layer's geometric quantity by 50%. Depth should therefore be based on the intended driveway section, not merely on the amount of material that happens to fit a delivery budget.
Layer count
The number of layers is shown as a planning record. Different courses may use different aggregate types and thicknesses, so the tool should not be interpreted as prescribing a universal driveway structure.
Limitations
This calculator estimates material quantity from user-entered geometry. It does not determine subgrade suitability, drainage, pavement design, required layer thickness or local construction standards.
Frequently Asked Questions
Can I calculate tonnes?
Yes.
Should I add an allowance?
A project-specific allowance is useful for grading and placement variability.
Does density vary?
Yes.
Does this design a driveway?
No.