How to use the gravel calculator
Enter the length and width of the area in feet (or the diameter of a round bed) and the depth in inches. Choose the material. The weight fills in with a typical value for that material; if your supplier quotes a different weight per yard, type it in, because that's the number they'll bill by.
For a base that you'll compact, such as crusher run under pavers or a shed, the compaction allowance adds extra: loose stone settles when it's compacted, so you need more than the finished volume. Decorative stone that isn't compacted needs none.
The formula
- Volume (cu ft) = length (ft) × width (ft) × depth (in) ÷ 12
- Cubic yards = cubic feet × (1 + compaction %) ÷ 27
- Tons = cubic yards × pounds per cubic yard ÷ 2,000
- Bags = cubic feet ÷ cubic feet per bag, rounded up
Weight per cubic yard by material
| Material | Lb per yd³ (used) | Tons per yd³ | Compaction allowance |
|---|---|---|---|
| Crushed stone (#57, clean) | 2,700 | 1.35 | none |
| Crusher run / road base | 3,000 | 1.5 | 15% |
| Pea gravel | 2,600 | 1.3 | none |
| River rock | 2,600 | 1.3 | none |
| Sand (dry) | 2,700 | 1.35 | 10% |
| Topsoil | 2,200 | 1.1 | 10% |
How far one cubic yard goes
| Depth | One cubic yard covers |
|---|---|
| 2 in | 162 sq ft |
| 3 in | 108 sq ft |
| 4 in | 81 sq ft |
| 6 in | 54 sq ft |
| 8 in | 41 sq ft |
| 12 in | 27 sq ft |
Worked examples
A pea gravel path
40 ft long, 3 ft wide, 3 in deep: 40 × 3 × 3 ÷ 12 = 30 cu ft. Divide by 27 = 1.11 yd³, about 1.44 tons. In 0.5 cu ft bags that's 60 bags, so bulk delivery makes sense.
A compacted shed base
12 × 10 ft, 4 in of crusher run after compaction: 40 cu ft finished. Adding 15% for compaction gives 46 cu ft = 1.7 yd³, about 2.56 tons. Without the allowance you'd order 1.48 yd³ and end up with a thin base.
Depth guide
- Decorative stone in beds: 2 to 3 in.
- Walkways: 3 to 4 in of surface stone, over a compacted base on soft ground.
- Patio or shed base: 4 to 6 in of compacted crusher run.
- Gravel driveway: 8 to 12 in total, built in layers.
Questions people ask
How much does a cubic yard of gravel weigh?
Most gravel and crushed stone weigh about 1.3 to 1.5 tons per cubic yard. Clean crushed stone is around 2,700 lb; crusher run, with its fines, can reach about 3,000 lb.
Is it cheaper to buy gravel in bags or bulk?
For anything past roughly one cubic yard, bulk is almost always cheaper, even with a delivery fee. 54 bags of 0.5 cu ft make one yard, and carrying them is real work.
Should I order extra?
Round up to the next half yard or the next ton. Suppliers rarely deliver less than a yard, and a little extra fills low spots.