Worked example: 4 inches deep
| Step | Math | Result |
|---|---|---|
| Area | 16 ft × 16 ft | 256 sq ft |
| Volume at 4 in | 256 × 4 ÷ 12 | 85.3 ft³ |
| Add 10% for compaction | 85.3 × 1.10 | 93.9 ft³ |
| Cubic yards | 93.9 ÷ 27 | 3.48 yd³ |
| Tons | 3.48 × 1.4 | 4.87 tons |
Gravel by depth
| Depth | Cubic feet (+10%) | Cubic yards | Tons | Bulk order (tons) | Delivered cost | 0.5 ft³ bags |
|---|---|---|---|---|---|---|
| 2 in | 42.7 | 1.74 | 2.43 | 2.5 | $212 | 94 bags / $517 |
| 3 in | 64.0 | 2.61 | 3.65 | 4.0 | $280 | 141 bags / $776 |
| 4 in | 85.3 | 3.48 | 4.87 | 5.0 | $325 | 188 bags / $1,034 |
| 6 in | 128.0 | 5.21 | 7.30 | 7.5 | $438 | 282 bags / $1,551 |
| 8 in | 170.7 | 6.95 | 9.73 | 10.0 | $550 | 376 bags / $2,068 |
At 4 inches, a bulk delivery is cheaper here ($1,034 in bags versus $325 delivered). Bagged gravel weighs about 9,400 lb in total for this size, so bulk is the practical way to buy for a driveway.
Prices used: bulk gravel $45 per ton plus $100 delivery (1 ton minimum); 0.5 ft³ bags $5.50. Quarry prices vary widely by stone type and region.
Patio base notes
Under pavers or flagstone, a compacted gravel base of 4 inches is typical for foot traffic, and 6 inches or more where soil is soft or frost is deep. The 1 in layer of bedding sand on top adds about 1.17 tons (sand for pavers by patio size).
For a patio finished with loose gravel instead of pavers, 2–3 inches of pea gravel over landscape fabric is enough: 2.4–3.6 tons here.
Nearby sizes
Also see 14×14 patio base , 12×16 patio base, or the driveway and patio gravel chart. Open the gravel calculator to change the size or price.