How to Calculate Gravel for a Driveway

Volume first

Measure the driveway's length and width in feet. Multiply them, then multiply by the depth in inches divided by 12. That's cubic feet. Divide by 27 to get cubic yards. A 60 ft × 10 ft driveway at 4 inches deep is 60 × 10 × 4 ÷ 12 = 200 cu ft, or about 7.4 cubic yards.

Then weight

Many suppliers sell gravel by the ton. To convert, multiply cubic yards by the material's density. Most gravel and crushed stone falls roughly between 1.3 and 1.5 US tons per cubic yard. At 1.4 tons per yard, 7.4 cubic yards is about 10.4 tons.

Density varies with stone type, size, and moisture, so ask your supplier for their figure. The CalcAndPlan Gravel Calculator lets you type in any density.

How deep should a driveway be?

A gravel driveway is usually built in layers rather than one thick pour of the same stone:

• Base layer: larger crushed stone, often 4–6 inches, compacted
• Middle layer (optional): medium crushed stone, about 4 inches
• Top layer: finer gravel for a smoother surface, 2–4 inches
• Resurfacing an existing driveway: often 2–3 inches of top stone

Calculating layers separately

Because each layer can have a different depth and density, calculate each one on its own and add them up. This also helps when ordering, since each layer is typically a separate material on the invoice.

Allow for compaction

Gravel loses volume as it's compacted with a roller or plate compactor and as vehicles drive on it. Adding 10–15% to the base layers is a common allowance. Check soil conditions too: a soft subgrade may need more base material or a geotextile fabric underneath.

Before you order

• Confirm whether the supplier prices by ton or by cubic yard
• Ask how much one truck carries and what the delivery fee is
• Plan where the truck can dump without damaging the lawn or a septic field
• Check local rules if the driveway connects to a public road