The formula
Cubic yards = length × width × depth (ft) ÷ 27 Tons = cubic yards × tons per cubic yard
Example: a 10 × 20 ft path, 4 inches deep, is 10 × 20 × 0.333 ÷ 27 = 2.47 cubic yards. At 1.4 tons per yard that is about 3.5 tons.
Quick answers for common sizes
| Area, 4 in deep | Cubic yards | Tons of gravel |
|---|---|---|
| 10 × 10 ft | 1.23 | 1.73 |
| 10 × 20 ft | 2.47 | 3.46 |
| 12 × 24 ft | 3.56 | 4.98 |
| 12 × 50 ft | 7.41 | 10.37 |
| 20 × 50 ft | 12.35 | 17.28 |
Typical weights
| Material | Tons per cubic yard |
|---|---|
| Gravel | 1.4 |
| Pea gravel | 1.35 |
| Crushed stone | 1.35 |
| River rock | 1.35 |
| Sand | 1.35 |
| Topsoil | 1.1 |
Weights change with stone size and moisture. If your supplier quotes a different figure, type it into Weight.
How deep to lay it
- 2 to 3 inches for walkways and decorative beds.
- At least 4 inches for a driveway topping. New driveways are often built 8 to 12 inches deep in layers, with larger stone at the bottom.
Sources and assumptions
Weights are typical figures for dry, loose material as sold by landscape suppliers. Wet material weighs more, so the supplier’s own number is always the one to use.
Questions
How many tons are in a cubic yard of gravel?
About 1.4 tons, roughly 2,800 lb, for ordinary gravel. Sand and crushed stone are a little lighter at about 1.35 tons.
How much area does a ton of gravel cover?
About 115 square feet at 2 inches deep, 77 square feet at 3 inches and 58 square feet at 4 inches.
How deep should a gravel driveway be?
At least 4 inches. New driveways are often built 8 to 12 inches deep in layers, with larger stone at the bottom.