Measure length times width in feet, then run (square feet × depth in inches) ÷ 324 to get cubic yards. If the driveway flares at the street or narrows past the house, take the widest and narrowest widths and use the average. Most Greater Boston gravel driveways get a 2–4 inch top coat over the existing base.
Worked example: 12 ft × 50 ft driveway
| Area | 12 × 50 = 600 sq ft |
| Top coat depth | 3 inches |
| Formula | 600 × 3 ÷ 324 = 5.6 cubic yards |
| Order | Round up to 6 yards — one full load |
Always round up to the next half or full yard; running short mid-project costs more than a little extra stone. Double-check with the material calculator, then pick your stone from the driveway gravel collection.
