Crushed Stone Calculator
Calculate tons of crushed stone for a base layer or drainage bed, using its 1.35 tons per cubic yard density, plus total cost.
How this calculator works
Crushed stone is sold by weight but measured by volume, so this calculator converts your length, width, and depth into cubic yards, then multiplies by crushed stone’s typical density of 1.35 tons per cubic yard to get the tons you need to order.
Formula: Cubic yards = (Length ft × Width ft × Depth ft) ÷ 27. Tons = Cubic yards × 1.35.
Worked example
A 20 ft × 10 ft base area at a 4-inch depth:
- Depth in feet: 4 ÷ 12 = 0.333 ft
- Cubic yards: (20 × 10 × 0.333) ÷ 27 ≈ 2.47 yd³
- Tons: 2.47 × 1.35 ≈ 3.33 tons
- At $45/ton, that’s $150.00 before waste.
Coverage reference
| Depth | Coverage per ton |
|---|---|
| 2 in | ~120 sq ft |
| 4 in | ~60 sq ft |
| 6 in | ~40 sq ft |
How to measure your area
Measure the length and width of the area to be covered in feet, and use the finished (compacted) depth you’re targeting rather than the loose depth you’ll actually spread, since crushed stone settles once compacted. For base layers under pavers or concrete, check your project’s spec for the required compacted thickness before calculating.
Frequently asked questions
How is crushed stone different from regular gravel?
Crushed stone is mechanically crushed from larger rock into angular, sharp-edged pieces, while gravel is often naturally rounded from water or weathering. The angular shape locks together better under load, which is why crushed stone is preferred for base layers and drainage.
Why does crushed stone weigh slightly less per yard than gravel?
This calculator uses 1.35 tons per cubic yard for crushed stone versus 1.4 tons for rounded gravel. Angular crushed stone particles don't nest together as tightly as smooth rounded gravel, leaving slightly more void space per yard, which makes it marginally lighter by volume.
What depth of crushed stone should I use?
A drainage layer under a patio or shed typically uses 2-4 inches. A structural base under a driveway or heavier paved surface usually calls for 4-6 inches, sometimes compacted in two lifts for depths over 4 inches.
Do I need to compact crushed stone after spreading it?
Yes, for any load-bearing base. Compacting with a plate compactor reduces the void space between angular particles and locks the layer together, which is the main reason crushed stone is chosen over gravel for driveways and paver bases in the first place.
Should I add extra for waste with crushed stone?
Yes — the waste toggle adds 10%, which is a reasonable allowance for compaction settling and spillage during spreading. Base layers in particular tend to compact down measurably from their loose-poured depth.
Estimates only. Verify quantities with your supplier before purchasing.