A gravel driveway that lasts is built in layers: large angular stone at the bottom for strength and drainage, a middle layer of smaller stone, and a top layer of dense-graded material (crusher run, also called crushed aggregate base) that compacts into a firm surface. This gravel driveway calculator works out the tons for each layer, the total and how many truckloads to order. A 50 × 12 ft driveway with 4 + 4 + 2 inches of stone takes about 28.5 tons.
Topping up an existing drive with one layer? The general gravel calculator is quicker. Thinking about paving instead? Compare the asphalt calculator.
How to use the gravel driveway calculator
- Enter the length and width. Single-lane driveways are usually 10 to 12 ft wide; allow extra at curves and the turnaround.
- Enter the depth of each layer. A common new-build profile is 4 to 6 inches of large base stone, 4 inches of mid-size stone and 2 to 4 inches of crusher run. Set a layer to 0 to skip it.
- Leave density at 1.4 tons per cubic yard unless your quarry gives a different figure; crushed stone typically ranges from about 1.3 to 1.5.
- Keep 10% or more for compaction and edges. Soft subgrade may need more base stone or a geotextile fabric underneath.
- Enter the size of truck your supplier uses to see how many deliveries to book, and an optional price per ton.
Formula
Worked example
A 50 × 12 ft driveway with a 4 inch base of #3 stone, 4 inches of #57 and 2 inches of crusher run, at 1.4 tons/yd³ plus 10%, delivered in 10-ton loads.
- Area: 50 × 12 = 600 ft².
- Base: 600 × 4 ÷ 12 = 200 ft³ = 7.41 yd³ × 1.10 = 8.15 yd³ × 1.4 = 11.4 tons. The middle layer is the same: 11.4 tons.
- Top: 600 × 2 ÷ 12 = 100 ft³ = 3.70 yd³ × 1.10 × 1.4 = 5.7 tons.
- Total: 28.5 tons (20.4 yd³), or 3 truckloads of 10 tons.
Tons of gravel per 100 feet of driveway
Total stone for each 100 ft of driveway at 1.4 tons/yd³ with 10% extra, by width and total depth of all layers.
| Driveway width | 4 in | 6 in | 8 in | 10 in | 12 in |
|---|---|---|---|---|---|
| 10 ft | 19.0 | 28.5 | 38.0 | 47.5 | 57.0 |
| 12 ft | 22.8 | 34.2 | 45.6 | 57.0 | 68.4 |
| 14 ft | 26.6 | 39.9 | 53.2 | 66.5 | 79.9 |
| 16 ft | 30.4 | 45.6 | 60.8 | 76.0 | 91.3 |
| 20 ft | 38.0 | 57.0 | 76.0 | 95.1 | 114.1 |
A typical 12 ft wide drive with 10 inches of stone needs about 57 tons per 100 ft, or six 10-ton loads.
Why layers matter
Road builders separate a strong, free-draining base from a tight surface course, and the same idea works for driveways. Large clean stone in the base spreads wheel loads and lets water drain; the dense-graded top layer has fines that bind into a hard crust. Penn State's Center for Dirt and Gravel Road Studies stresses drainage and a crowned surface, so water runs off rather than soaking into the base. Crown the driveway about half an inch per foot of width from the center, or slope it to one side, and keep ditches or swales clear.
Maintenance and upgrades
Expect to add a thin top-up layer every few years as stone is pushed aside and pressed in; enter only a top layer of 1 to 2 inches to price it. If you later pave, the compacted stone becomes the base for asphalt. Once paved, the driveway sealer calculator estimates sealcoat. For decorative borders, see the landscape rock calculator.
Caveats and assumptions
- Stone density varies with rock type, size and moisture. Ask your quarry for its tons-per-yard figure.
- Layer names and sizes (#3, #57, #411, crusher run) vary by region. Ask your supplier which products they recommend for each layer.
- Soft or clay subgrades may need excavation, geotextile fabric or more base stone. This calculator does not assess soil.
- Delivery fees and minimum loads often matter more than the price per ton for small orders.
Frequently asked questions
How much gravel do I need for a driveway?
Multiply length × width × total depth in feet, divide by 27 for cubic yards, then multiply by about 1.4 for tons. A 50 × 12 ft driveway with 10 inches of stone needs about 18.5 yd³, or 28.5 tons with 10% extra.
How thick should a gravel driveway be?
New driveways are commonly built 8 to 12 inches thick in two or three layers. Driveways on firm soil carrying only cars can be thinner; soft soil or heavy trucks need more.
How many tons of gravel are in a truckload?
It depends on the truck. Small single-axle dump trucks often carry about 5 to 8 tons and tandem-axle trucks about 10 to 15 tons. Your supplier will tell you their load sizes.
What is the best top layer for a gravel driveway?
A dense-graded crushed stone with fines, often sold as crusher run, crushed aggregate base or #411, packs into a firm surface. Rounded pea gravel stays loose and is better for paths.
How many tons of gravel for a 100 ft driveway?
For 12 ft wide and 10 inches of stone, about 57 tons with 10% extra at 1.4 tons per cubic yard.
Sources
- Penn State Center for Dirt and Gravel Road Studies — gravel road drainage, crown and aggregate surfaces
- Pavement Interactive — pavement reference — aggregate base and dense-graded aggregate
- NIST — Unit Conversion — cubic feet to cubic yards
This calculator gives estimates for planning and education. Check measurements, local codes, supplier specs and your school's official policy before relying on a result. See our disclaimer and how we build and check calculators.