Quick answer: cubic yards = length × width × depth (ft) ÷ 27, then tons = yards × 1.35. A 12 × 40 ft driveway at 4 inches needs 5.93 yards ≈ 8 tons. Add 10–15% because loose stone compacts.
How far does a ton of gravel go?
A ton is roughly 0.74 cubic yards, or 20 cubic feet. Coverage depends entirely on depth:
| Depth | ft² per ton | ft² per cubic yard | yd³ per 100 ft² |
|---|---|---|---|
| 1 in | 240 | 324 | 0.31 |
| 2 in | 120 | 162 | 0.62 |
| 3 in | 80 | 108 | 0.93 |
| 4 in | 60 | 81 | 1.23 |
| 6 in | 40 | 54 | 1.85 |
| 8 in | 30 | 40 | 2.47 |
The right-hand column is the fastest estimate on the page: area ÷ 100 × the figure shown. A 480 ft² driveway at 4 inches is 4.8 × 1.23 ≈ 5.9 cubic yards.
Which stone, and how deep
| Material | Size | Best for | Depth |
|---|---|---|---|
| Crusher run / road base | 0–¾ in with fines | Compacting base layer | 4–6 in |
| #57 crushed stone | ¾ in, clean | Driveway top, drainage | 2–4 in |
| Pea gravel | ⅜ in rounded | Paths, decorative | 2–3 in |
| #8 / chip stone | ⅜ in angular | Driveway surface | 2 in |
| Limestone screenings | Dust to ¼ in | Paver bedding, compacts hard | 1 in |
| River rock | 1–3 in rounded | Decorative, drainage beds | 2–3 in |
The distinction that matters most: angular stone with fines locks together and compacts into a stable surface, while clean rounded stone like pea gravel never does — it stays loose and migrates underfoot. Build driveway bases from crusher run and save the rounded stone for decoration.
Building a gravel driveway
A driveway that lasts is built in layers, not dumped in one lift. For a 12 × 40 ft drive (480 ft²):
- Base — 4 in of crusher run: 480 × 0.333 ÷ 27 = 5.93 yd³ ≈ 8 tons. Compact it before going further.
- Top — 2 in of #57 stone: 480 × 0.167 ÷ 27 = 2.96 yd³ ≈ 4 tons.
- Total: about 12 tons, plus 10–15% for compaction — order roughly 13.5 tons.
On soft or clay subgrades, add a geotextile fabric underneath and a deeper base. Without it, stone migrates down into the soil and the driveway needs topping up every couple of years.
Common mistakes & pro tips
- Ordering the finished depth. Loose stone compacts 10–15%. Order the loose volume.
- Depth left in inches. Convert to feet, or use the unit selector on the depth field.
- Confusing yards and tons. Suppliers quote stone by the ton; multiply yards by about 1.35.
- Rounded stone for a driveway surface. Pea gravel looks good and drives badly — it never locks together.
- Pro tip — check pickup payload. A cubic yard of stone is 2,700 lb. Most half-ton pickups are at their limit with well under a yard.
- Pro tip — paving over the base. If this stone is the sub-base for a sealed surface rather than the finished top, work out the wearing course separately with the asphalt volume calculator, which prices in tons of hot mix and its own compaction factor.
- Pro tip — measure the delivery. Dumped loads form a rough cone. Measure its base diameter and height and use the cone calculator to check you got what you paid for.
Frequently asked questions
How much gravel do I need for a driveway?
Multiply length × width × depth in feet and divide by 27 for cubic yards. A 12 × 40 ft driveway at 4 inches deep needs 160 ft³, or 5.9 cubic yards — about 8 tons of crushed stone. Most gravel driveways are built in two or three layers totalling 6 to 8 inches.
How many tons is a cubic yard of gravel?
About 1.35 tons, or 2,700 pounds, for typical crushed stone at 100 lb per cubic foot. Pea gravel and limestone screenings run slightly heavier at around 1.42 tons per yard. Suppliers usually sell stone by the ton, so this conversion is the one you need at the order desk.
How deep should gravel be?
For decorative stone over landscape fabric, 2 to 3 inches. For a walkway base, 4 inches. For a car driveway, 6 to 8 inches total, usually built as a 4-inch base layer of larger stone with 2 to 4 inches of smaller stone on top. Soft or clay subgrades need more.
How much area does a ton of gravel cover?
A ton of gravel is about 0.74 cubic yards, or 20 cubic feet. Spread 2 inches deep that covers roughly 120 square feet; at 3 inches about 80 square feet; at 4 inches about 60 square feet. Coverage halves as you double the depth.
Should I order extra gravel for compaction?
Yes — plan on 10 to 15 percent extra. Crushed stone delivered loose settles substantially once spread and compacted, so a 4-inch loose layer finishes closer to 3.5 inches. Ordering the finished depth without an allowance leaves you short.