How gravel is calculated
Landscape suppliers often sell by volume and quarries by weight, so it helps to have both figures.
Volume (ft³) = length × width × (depth in inches ÷ 12)
Volume to order = volume × (1 + extra %)
Weight (lb) = volume to order × material weight per ft³
Tons = lb ÷ 2,000Worked example: a 20 × 10 ft path, 3 in deep, in crushed stone
- Volume: 20 × 10 × (3 ÷ 12) = 50 ft³.
- With 10% extra for settling: 55 ft³, or 2.04 yd³.
- Weight at about 100 lb per ft³: 5,500 lb, or 2.75 tons.
- In 50 lb bags: 5,500 ÷ 50 = 110 bags.
At this size, bags mean moving 110 separate loads, so bulk delivery is usually worth pricing.
Typical gravel weights
| Material | Lb per ft³ used here | Tons per yd³ |
|---|---|---|
| Pea gravel | 95 | About 1.28 |
| Crushed stone | 100 | About 1.35 |
| Road base mix | 110 | About 1.49 |
Real weights vary with rock type, moisture and compaction. If your supplier quotes a weight per yard, go by that figure, particularly when you're ordering by the ton.
Common depths
Depth depends on the job, soil and local climate, so treat these as starting points. Garden paths and decorative beds often use about 2–3 in. Patio bases are commonly 4–6 in of compacted material. Driveways usually need thicker, layered construction, often around 8 in or more, particularly on soft ground. Ask a local supplier what works in your area.
Before the delivery arrives
- Ask for a dump location, and check that the truck can reach it without crossing a septic system or soft lawn.
- Confirm the minimum load, the delivery fee and whether the price is per ton or per yard.
- Compact base layers in stages rather than all at once. Compaction reduces volume, so allow extra.
- Add edging and landscape fabric where you need them. Both are extra.
Pouring a slab over the base? Use the concrete calculator next.