Gravel Calculator
See the depth guide below.
Crushed stone ≈ 2700 · Gravel / crushed rock ≈ 2800 · Pea gravel ≈ 2900 · Sand ≈ 2700
Loose material settles once compacted — order a little extra.
Order this much
7.6 tons
- Cubic yards (before compaction)
- 4.94 yd³
- Ordering volume (incl. 10% compaction)
- 5.43 yd³
- Area covered
- 400 ft²
- Volume
- 133.33 ft³
Cost comparison
$342.22 by ton vs $325.93 by yd³
- By the ton
- $342.22
- By the cubic yard
- $325.93
- Verdict
- Buying by the cubic yard is cheaper here
How deep should gravel be?
| Where | Depth | Note |
|---|---|---|
| Garden path / walkway | 2 in | Just enough to cover fabric |
| Patio or seating area | 3 in | Comfortable to walk on |
| Driveway surface | 4 in | Over a compacted base |
| Driveway base layer | 6 in | Heavy loads need the depth |
Tonnage depends entirely on density, and density varies with stone type, moisture, and how well it was compacted — treat the numbers as an order estimate and confirm against your supplier's ticket. Widths here assume a rectangular area. Covering beds with a lighter material? Use the mulch calculator, which quotes in bags and cubic yards.
A 40 × 10 ft driveway at 4 inches deep needs 5.43 cubic yards ordered (4.94 exact, plus a 10% compaction allowance) — and at a typical 2,800 lb per cubic yard that's 7.6 tons, which is how suppliers actually sell it. At the placeholder prices here, buying by the yard costs $325.93 against $342.22 by the ton, so the per-yard quote wins on this job. Change the material and the tonnage moves even when the volume doesn't.
Tons, not just yards
Gravel and crushed stone are quarried by weight and delivered by dump truck, so the number on your invoice is tons. Getting there takes one extra step:
area (ft²) = length (ft) × width (ft)
volume (ft³) = area × (depth in ÷ 12)
cubic yards = volume ÷ 27
order (yd³) = cubic yards × (1 + compaction%)
tons = order (yd³) × density (lb/yd³) ÷ 2,000
Worked example — the page default, a 40 × 10 ft driveway at 4 inches, general gravel at 2,800 lb/yd³:
- Area: 40 × 10 = 400 ft²
- Volume: 400 × (4 ÷ 12) = 133.33 ft³ → 4.94 yd³
- Add 10% compaction: 5.43 yd³ to order
- Weight: 5.43 × 2,800 ÷ 2,000 = 7.6 tons
Same area, different jobs
| Job | Size & depth | Exact volume | Order (+10%) | Tons | By ton vs by yard |
|---|---|---|---|---|---|
| Garden path | 20 × 3 ft, 2 in | 0.37 yd³ | 0.41 yd³ | 0.57 | $25.67 vs $24.44 |
| Patio base | 12 × 12 ft, 3 in | 1.33 yd³ | 1.47 yd³ | 2.05 | $92.40 vs $88.00 |
| Driveway (default) | 40 × 10 ft, 4 in | 4.94 yd³ | 5.43 yd³ | 7.6 | $342.22 vs $325.93 |
| Driveway base layer | 40 × 10 ft, 6 in | 7.41 yd³ | 8.15 yd³ | 11.41 | $513.33 vs $488.89 |
All rows use 2,800 lb/yd³ and the placeholder prices of $45 per ton and $60 per cubic yard. Buying by the yard looks cheaper in every row here only because those two placeholder numbers happen to sit that way — the point of showing both is that suppliers quote one or the other, and you can't compare them in your head.
Density is the input that decides your tonnage
Two yards of different materials weigh different amounts. The calculator uses these typical values as a starting point, and the field is editable on purpose:
| Material | Typical density |
|---|---|
| Crushed stone (driveway base) | 2,700 lb/yd³ |
| Gravel / crushed rock (general) | 2,800 lb/yd³ |
| Pea gravel (walkways, play areas) | 2,900 lb/yd³ |
| Sand (paver base, leveling) | 2,700 lb/yd³ |
Pea gravel at the default driveway's 4 inches would weigh more than the general gravel above, even though the volume is identical. These are typical supplier figures, not specifications — moisture content and source rock move real weights by several percent, and the number that settles the bill is the one on the delivery ticket.
The inputs people get wrong
- Depth. 2 inches covers a walkway over landscape fabric; 3 inches is comfortable underfoot on a patio; 4 inches is a driveway surface over a compacted base; 6 inches is a base layer under heavy loads. On the default driveway, 4 → 6 inches is 7.6 → 11.41 tons.
- Compaction. Loose material settles. The default 10% allowance covers normal spreading and tamping; drop it toward 5% if you're compacting in lifts with a plate compactor, and raise it for loose, un-compacted fills. Turning it off entirely takes the default job from 7.6 to 6.91 tons — which is how people end up short by half a ton.
- Units. Depth is inches, dimensions are feet. Writing 4 inches as 0.4 ft overstates the depth by 20%.
How to use this calculator
- Enter length and width in feet.
- Set depth in inches — 2 for paths, 4 for driveways, 6 for base layers.
- Pick the material, or type the density from your supplier's spec sheet.
- Set the compaction allowance (10% by default).
- Enter your prices per ton and per cubic yard, then compare the two totals.
Frequently asked questions
How many tons of gravel do I need for my driveway?
For the default 40 × 10 ft driveway at 4 inches: 7.6 tons (5.43 yd³ at 2,800 lb/yd³). At 6 inches for a base layer it's 11.41 tons.
How many cubic yards are in a ton of gravel?
About 0.71 yd³ at 2,800 lb/yd³ — a cubic yard weighs roughly 1.4 tons. The conversion flips with density, so use the material's figure rather than a rule of thumb.
How deep should a gravel driveway be?
4 inches of surface gravel over a compacted base is the common specification; 6 inches (or more, in lifts) for the base layer itself under vehicle loads. Paths and patios need 2–3 inches.
Why does the calculator add a compaction allowance?
Because loose gravel settles and spreads. Ordering exact volume leaves you short by the time it's compacted — at the default 10%, the 4.94 yd³ job becomes 5.43 yd³, and skipping it would under-order by about 0.7 tons.
Should I buy by the ton or by the cubic yard?
Whichever your supplier quotes, then convert. Enter both prices and compare: with the placeholders here, per-yard pricing comes out $16.29 cheaper on the default driveway. The comparison is only as good as the prices you type in.
Does pea gravel weigh the same as crushed stone?
No — pea gravel runs about 2,900 lb/yd³ against roughly 2,700 lb/yd³ for crushed stone, so the same volume is meaningfully heavier. Moisture and source rock change it further; the delivery ticket is the final word.
Data sources: Volumes are geometry from the dimensions you enter (27 ft³ = 1 yd³); tonnage uses a 2,000 lb short ton. Density values (crushed stone ≈ 2,700, gravel ≈ 2,800, pea gravel ≈ 2,900, sand ≈ 2,700 lb/yd³) are typical figures published by aggregate suppliers and vary with material, moisture, and source — use your supplier's spec or the weight on the delivery ticket. Depth guidance (2 in paths, 3 in patios, 4 in driveway surfaces, 6 in base layers) is standard construction practice, not a code requirement. $45 per ton and $60 per cubic yard are placeholders, not market quotes. Every figure on this page was produced by this calculator and can be reproduced with the same inputs. Related tools: mulch calculator, concrete calculator, tile calculator, all home project calculators, percentage increase calculator.