How many tons of rock
do you need?
Enter the length, width and depth, pick the rock, and get cubic yards and tons. It’s a planning estimate for talking to a supplier or to us, not a delivery order.
Enter a length, width and depth to see your estimate.
How the numbers work
Cubic feet = length (ft) × width (ft) × depth (in) ÷ 12. Cubic yards = cubic feet ÷ 27. Tons = cubic yards × the material’s weight per yard. Then we add your compaction and waste allowance.
Example: a 200 ft by 12 ft drive with a 3” top coat is 200 × 12 × 3 ÷ 12 = 600 cubic feet, or about 22 cubic yards. At roughly 1.4 tons per yard that’s about 31 tons, and with 15% extra, about 36 tons.
Why yards and tons don’t match
Rock is usually sold by the ton, but job sizes are figured in cubic yards. The weight of a cubic yard changes with the rock, the moisture and the quarry, which is why we show a range. The number on your supplier’s scale ticket is the one that counts.
How much can a dump truck carry?
Here’s the part that surprises most people: a truck runs out of weight long before it runs out of space. A bed that holds 14 cubic yards of mulch can’t legally carry 14 cubic yards of rock, because rock weighs about 1.4 tons per yard and the truck has a weight limit. That’s why loads of rock are quoted in tons, not just yards.
These are typical figures. Every truck and every legal weight limit is a little different, so your hauler’s number is the one to use.
| Truck | Typical rock load | About how many yards | Good for |
|---|---|---|---|
| Pickup or small trailer | Up to about 1 ton (check your payload sticker) | About ¾ yard | Small repairs, a few wheelbarrows |
| Small dump truck (single axle) | About 6–8 tons | About 4–6 yards | Short drives, paddock spots, tight sites |
| Tandem dump truck | About 12–16 tons | About 9–11 yards | Most driveways, pads and paddocks |
| Tri-axle or larger | About 18–22 tons | About 13–16 yards | Long drives, big pads, bulk base rock |
What to know about deliveries
- Loads are rarely exact. Plan on a whole number of loads, or a partial last load. Ask whether there’s a minimum order or a short-load fee.
- Access matters. A full dump truck needs a firm, wide way in, room to turn and clearance overhead. A large truck on a soft or narrow drive can damage it, or get stuck.
- Where it’s dumped. A truck drops the load in one pile. Spreading it into a finished surface is the work, so ask where it should land and how it will get moved.
- Delivery cost. It usually depends on distance and load size, not only the rock. Get both numbers.
Planning weights by material
These are typical planning values, in tons per loose cubic yard. Your supplier’s figure may differ.
| Material | Tons per cubic yard | Typical extra |
|---|---|---|
| 3/4 minus, 5/8 minus, 1-1/2 minus (road base) | About 1.4 | 10–15% (it compacts) |
| 2 to 4 minus | About 1.45 | 10–15% |
| 3/4 clean, 3/4 to 1-1/2 drain rock | About 1.3 | 0–10% (it doesn’t pack) |
| Pea gravel, river rock | About 1.35–1.4 | 5–10% |
| Quarry spalls | About 1.4 | 10% |
| Pit run | About 1.5 | 10–15% |
| Fill dirt | About 1.3 | 10–20% (it settles) |
| Topsoil | About 1.1 | 5–10% |
Typical depths
- Driveway: a 4–6” base of 1-1/2 minus, plus a 2–3” cap of 3/4 minus.
- Shop, RV or equipment pad: a 6” or deeper base, capped with compacted 3/4 minus.
- Paddock: a 4–6” base and at least 6” of 5/8 minus footing.
- Walkway: 3–4” of 3/4 minus under a 1/4 or 3/8 minus top.
Depths are starting points. Soft or wet ground needs more, and we’ll tell you what your site calls for. If you’re not sure which rock to pick, read our rock and gravel size guide.
Questions
How do I calculate how much gravel I need?
Multiply length by width in feet, multiply by depth in inches divided by 12, and divide by 27 to get cubic yards. Multiply by about 1.4 for crushed rock to estimate tons, then add 10 to 15 percent for compaction and waste.
How many tons are in a cubic yard of gravel?
Crushed rock such as 3/4 minus is usually around 1.3 to 1.5 tons per cubic yard. Clean drain rock is a little lighter and pit run a little heavier. Weight varies by quarry and moisture, so use your supplier’s number.
How much rock fits in a dump truck?
It depends on the truck, but weight is the limit, not space. A small single-axle dump carries roughly 6 to 8 tons of rock, a tandem about 12 to 16 tons and a tri-axle about 18 to 22 tons. Ask your hauler for the exact figure.
Why do I need extra rock for compaction?
Rock with fines packs down when it’s compacted, so a delivered cubic yard covers less finished depth than you’d calculate. Adding 10 to 15 percent makes up for that and for waste.
Want it figured and delivered?
Send the area and what it’s for. We’ll confirm the rock, the depth and the tons in writing.