DRIVEWAY
How much gravel for a driveway?
Work out each layer separately, then add the layers. A gravel driveway is normally built in more than one course — a coarse base that carries the load and a finer surface course that you drive on — and each has its own depth. Multiplying one depth by the whole area gives the wrong order for both.
The arithmetic per layer is the same as anywhere else on this site: cubic yards = square feet × depth in inches ÷ 324.
Worked example
A 12 ft × 50 ft driveway is 600 sq ft. Suppose the plan calls for a base course and a surface course:
- Base course, 4 inches: 600 × 4 ÷ 324 = 7.41 cubic yards
- Surface course, 2 inches: 600 × 2 ÷ 324 = 3.70 cubic yards
- Total: 11.11 cubic yards, before any allowance for compaction and spreading loss
Compaction is the part that catches people out, and it is why the base figure is not the same as the finished thickness: a compacted base course needs more loose material than its finished depth suggests, because the rolling squeezes the air out. Ask the supplier or your contractor what loose depth their product needs to finish at your specified thickness — that factor is product specific and this page will not invent one.
Why this page will not give you a depth
Driveway depths depend on what is underneath the driveway and what will drive on it — a car on firm subgrade, a delivery truck on soft ground, and a track over clay are three different builds. Local requirements sometimes specify them. Gradation matters too: a base course and a surface course are different products with different names, and ordering the surface product for the base layer is a common and expensive mistake.
So the honest version is: get the depths and the product names from your plan, your contractor or your local requirements, then use this page for the volume arithmetic. It will not print a depth table it cannot stand behind.
Ordering checklist for a driveway
- Length and width in feet, measured along the actual drive including any apron or turning area.
- Each course separately, with its own depth and its own product name.
- Compaction allowance, from the supplier, for any course that will be rolled.
- Spreading loss — a small percentage is normal; decide it rather than accepting one silently.
- Access and delivery. A loaded delivery truck needs somewhere to tip, and a yard of gravel is well over a ton of material. Where the pile lands is part of the order.
- Edging or containment, because loose gravel at the edges migrates into lawns and drains.
Tons, again
If the quote comes back in tons, the conversion needs the density of the specific aggregate — see the tonnage note on the gravel calculator. Ask for pounds per cubic yard for that product and do the multiplication yourself; a density taken from a different gradation can be far enough out to change the load count.
Related calculators
Gravel calculator · Pea gravel calculator for the small-bag, path-and-border case · Mulch calculator for the same volume arithmetic.
The arithmetic is from the definitions 1 cubic yard = 27 cubic feet and 1 foot = 12 inches. Depths and compaction factors are deliberately left to your project's own specification.