How the crushed stone calculator works
Volume first, weight second:
- Cubic yards = length (ft) × width (ft) × depth (in) ÷ 12 ÷ 27
- Tons = cubic yards × about 1.35 (clean crushed stone)
Example. A 12 × 12 ft pad, 4 inches deep: 144 × 0.333 = 48 cubic feet = 1.78 cubic yards = about 2.4 tons. With 10 percent extra, order about 2 cubic yards or 2.6 tons.
Crushed stone sizes
Many US quarries number their stone using the AASHTO/ASTM size system. Larger numbers mean smaller stone.
| Size | Approx. stone size | Common uses |
|---|---|---|
| #1 | 2–4 in | Construction entrances, very soft ground |
| #3 | 1–2 in | Driveway base layer, drainage |
| #57 | about 3/4 in (1/2–1 in) | Drainage, driveway middle layer, under slabs, pipe bedding. See the #57 stone calculator |
| #67 | 3/8–3/4 in | Concrete aggregate, drainage, walkways |
| #8 | about 3/8 in | Paver bedding in some areas, walkways |
| #10 / screenings | dust to 1/4 in | Leveling, setting stone |
| Crusher run / 3/4 minus | 3/4 in down to dust | Compacted base. See the crusher run calculator |
Names vary a lot by region (some states use their own numbers), so describe the job to your supplier and ask for the matching product.
How deep to lay crushed stone
| Project | Depth |
|---|---|
| Walkway base | 3–4 in compacted |
| Patio or paver base | 4–6 in compacted |
| Shed or hot tub pad | 4–6 in compacted |
| Driveway base layer | 4–6 in, plus upper layers. See the driveway gravel calculator |
| Under a concrete slab | 4 in is common; follow your plans or local code |
Crushed stone weight and coverage
| Stone | Tons per cubic yard (about) | Sq ft per ton at 3 in | Sq ft per ton at 4 in |
|---|---|---|---|
| Clean crushed stone (#57, #67) | 1.35 | 80 | 60 |
| Larger base stone (#3) | 1.3–1.4 | about 80 | about 60 |
| Crusher run (with fines) | 1.5 | 72 | 54 |
Ordering tips
- Compaction. Compacted stone takes up less room than loose stone. For a base you will run a plate compactor over, add 10 to 20 percent.
- Washed vs. unwashed. Washed stone has the dust removed. It drains better and looks cleaner; unwashed is fine for bases that will be covered.
- Limestone, granite or trap rock. The rock type changes the color and slightly the weight. Granite and trap rock are a little heavier than limestone.
Figures are typical for dry, loose crushed stone. Your quarry's published weight per yard beats any average.
Questions people ask
- How much does a cubic yard of crushed stone weigh?
- Clean crushed stone such as #57 weighs about 2,400 to 2,700 pounds per cubic yard loose, or roughly 1.2 to 1.35 tons. Stone with fines in it, like crusher run, is heavier, about 1.5 tons.
- How many square feet does a ton of crushed stone cover?
- About 80 square feet at 3 inches deep and about 60 square feet at 4 inches, using 1.35 tons per cubic yard.
- What size crushed stone should I use for a base?
- For a compacted base under pavers, a shed or a patio, use a stone with fines such as crusher run or 3/4 minus. For a base that must drain, such as under a driveway or around a drain pipe, use clean stone like #57.
- Is crushed stone the same as gravel?
- Not quite. Gravel often means naturally rounded stone from riverbeds or pits; crushed stone is mechanically broken and has sharp faces, so it locks together better under load.