Gravel formula
Cubic yards = Length (ft) × Width (ft) × Depth (in) ÷ 12 ÷ 27
Tons = Cubic yards × Density (tons per yd³)
Tons = Cubic yards × Density (tons per yd³)
Example: A 20 × 10 ft path, 4 inches deep, needs 66.7 cubic feet — 2.47 cubic yards. At 1.4 tons per yard, that is about 3.46 tons of pea gravel (3.14 metric tonnes).
Typical densities
- Pea gravel ≈ 1.4 t/yd³ · Crushed stone ≈ 1.35 t/yd³
- River rock ≈ 1.3 t/yd³ · Road base / crusher run ≈ 1.5 t/yd³
- Sand ≈ 1.35 t/yd³ · Topsoil ≈ 1.1 t/yd³
Building a patio? The paver base calculator adds bedding sand and paver counts.
Frequently asked questions
How do I calculate how much gravel I need?
Length × width × depth (in feet) gives cubic feet; divide by 27 for cubic yards; multiply by the material density for tons. A 20 × 10 ft area 4 inches deep is 2.47 cubic yards, about 3.5 tons of pea gravel.
How many tons are in a cubic yard of gravel?
Typically 1.3 to 1.5 tons (2,600–3,000 lb), depending on stone size and moisture. Pea gravel is about 1.4 tons per cubic yard.
How deep should a gravel driveway be?
About 4–6 inches of compacted base plus 2–3 inches of surface gravel, so 8–12 inches in total on soft ground.
How much does a ton of gravel cover?
At 2 inches deep, one ton of pea gravel covers roughly 115 sq ft; at 4 inches, about 58 sq ft.