The short answer
To find how much gravel you need, multiply length × width × depth in feet to get cubic feet, then divide by 27 for cubic yards. Multiply cubic yards by about 1.4 to get tons for crushed stone or pea gravel. A 20 × 10 ft path 3 inches deep needs 1.85 cubic yards, or about 2.6 tons. Add 5–10% for compaction and uneven ground.
How the calculation works
Gravel is measured by volume and sold by volume or weight. The calculator finds the volume of the area at the depth you choose, adds your allowance for compaction and waste, then converts the volume to weight using the density of the material.
- Volume = area × depth
- With extra = volume × (1 + extra % ÷ 100)
- Weight = volume × density
In US units, divide cubic feet by 27 to get cubic yards. In metric, the volume is already in cubic metres.
Worked example
A 20 × 10 ft path, 3 inches deep, in crushed stone with 5% extra:
- 20 × 10 × (3 ÷ 12) = 50 cubic feet
- 50 × 1.05 = 52.5 cubic feet = 1.94 cubic yards
- 1.94 × 1.4 tons = 2.72 tons
Typical weights by material
| Material | Tons per cu yd | Pounds per cu yd | kg per m³ |
|---|---|---|---|
| Crushed stone (#57) | 1.40 | 2,800 | 1,661 |
| Pea gravel | 1.40 | 2,800 | 1,661 |
| River rock | 1.35 | 2,700 | 1,602 |
| Crusher run / road base | 1.50 | 3,000 | 1,780 |
| Sand (dry) | 1.35 | 2,700 | 1,602 |
These are typical dry, loose figures. Moisture and the size mix of the stone change them by about 10% either way. If your supplier quotes a different density, choose Custom density and enter it.
How much gravel for common projects
Crushed stone at 1.4 tons per cubic yard, before any extra:
| Project | Size | Depth | Cubic yards | Tons |
|---|---|---|---|---|
| Garden path | 3 × 30 ft | 2 in | 0.56 | 0.78 |
| Patio base | 12 × 12 ft | 4 in | 1.78 | 2.49 |
| Shed pad | 10 × 12 ft | 4 in | 1.48 | 2.07 |
| Parking pad | 10 × 20 ft | 4 in | 2.47 | 3.46 |
| Driveway top layer | 12 × 50 ft | 6 in | 11.11 | 15.56 |
Recommended depths
- Decorative beds and paths: 2–3 inches. Deeper pea gravel is hard to walk on.
- Patio and shed bases: 4 inches of compacted crushed stone under pavers or a slab.
- Driveways: 8–12 inches in total, built in compacted layers with the coarsest stone at the bottom.
- French drains: fill the trench around the pipe; calculate trench length × width × depth.
Tips before you order
- Lay landscape fabric first under paths and decorative gravel to slow weeds and stop the stone sinking into the soil.
- Order a little extra. A second delivery usually costs more than the leftover stone.
- Check delivery minimums. Many suppliers charge a flat delivery fee, so it can be cheaper to order everything at once.
Frequently asked questions
How many tons are in a cubic yard of gravel?
Most gravel and crushed stone weighs about 1.4 tons (2,800 lb) per cubic yard when dry. Crusher run and road base are heavier at around 1.5 tons, and wet gravel weighs more still. Ask your supplier for their scale figure if you are ordering by the ton.
How much area does a ton of gravel cover?
A ton of crushed stone (about 0.71 cubic yards) covers roughly 115 square feet at 2 inches deep, 77 square feet at 3 inches, or 58 square feet at 4 inches.
How deep should gravel be for a driveway?
A gravel driveway is usually built in layers totalling 8 to 12 inches, with larger stone at the bottom and a 2 to 4 inch top layer. Paths and decorative beds only need 2 to 3 inches.
Should I order gravel by the ton or by the yard?
Quarries usually sell by the ton; landscape yards often sell by the cubic yard. This calculator gives both, so you can compare prices either way.
Why add extra for compaction?
Loose stone settles when it is driven on or compacted with a plate compactor. Base layers such as crusher run can lose 10–15% of their loose volume, so order more than the bare volume.
Sources
Related calculators
About this calculator. Every formula on this page is tested against worked examples from the sources above before publishing. Results are estimates for planning; confirm with your supplier or local code.
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