How This Calculator Works
The calculator multiplies your area (length x width, or circle area, or custom square footage) by depth to get cubic feet. It then converts to cubic yards (divide by 27) and tons using the density of your selected gravel type. Pea gravel and crushed stone weigh roughly 2,700 lbs per cubic yard, while decomposed granite is lighter at around 2,500 lbs per cubic yard.
Gravel Depth Guide
| Project | Recommended Depth | Gravel Type |
|---|---|---|
| Driveway | 4-6 inches | Crushed stone (#57 or #411) |
| Walkway / Path | 2-3 inches | Pea gravel or decomposed granite |
| Patio base | 4 inches | Crushed stone (#21A) |
| French drain | 6-8 inches | Washed #57 stone |
| Garden border | 2-3 inches | River rock or pea gravel |
| Under pavers | 4-6 inches | Crushed stone base (#21A) |
Gravel Types Compared
| Type | Size | Weight (lbs/yd³) | Cost (per yd³) | Best For |
|---|---|---|---|---|
| Pea Gravel | 3/8" | ~2,700 | $35-55 | Paths, patios, play areas |
| Crushed Stone | 3/4"-1" | ~2,700 | $35-50 | Driveways, base material |
| River Rock | 1"-3" | ~2,650 | $45-75 | Decorative, dry creek beds |
| Decomposed Granite | Fine (1/4") | ~2,500 | $40-60 | Paths, rustic patios |
Coverage Per Ton
One ton of gravel covers roughly 100 square feet at 2 inches deep, 80 square feet at 3 inches, and 50 square feet at 4 inches. These numbers vary slightly by gravel type — lighter materials like decomposed granite cover a bit more area per ton than dense river rock.
| Depth (inches) | Coverage per Ton (sq ft) | Coverage per Cu Yd (sq ft) |
|---|---|---|
| 1" | ~200 | ~324 |
| 2" | ~100 | ~162 |
| 3" | ~65 | ~108 |
| 4" | ~50 | ~81 |
| 6" | ~35 | ~54 |
FAQ
How many tons of gravel do I need for a 2-car driveway?
A typical 2-car driveway is 16 x 40 feet (640 sq ft). At 4 inches deep, that is about 8 cubic yards or roughly 10-11 tons of crushed stone. Budget $350-550 for material, plus $100-150 for delivery.
Should I use crushed stone or pea gravel for a driveway?
Crushed stone locks together and stays in place under vehicle weight. Pea gravel shifts and spreads, making it a poor choice for driveways. Use crushed stone #57 or #411 for driveways and pea gravel for walkways and patios where foot traffic is the only load.
Do I need landscape fabric under gravel?
For decorative areas and walkways, landscape fabric prevents weeds from growing through. For drainage applications, skip the fabric — it can clog over time. For driveways, geotextile fabric under the base layer prevents the gravel from sinking into soft soil.
How thick should a gravel base be for pavers?
For pedestrian traffic (patios, walkways), use 4 inches of compacted crushed stone base. For driveways, increase to 6-8 inches. Always add 1 inch of leveling sand on top of the compacted base before setting pavers.
Related Calculators
- Soil Volume Calculator — for garden beds and raised planters
- Mulch Calculator — for landscape beds and tree rings
- Landscape Rock Calculator — for decorative stone like lava rock, flagstone, and boulders
- Retaining Wall Calculator — for block walls that need gravel backfill
Prices shown are approximate 2026 U.S. averages and may vary significantly by region, retailer, and market conditions. Always get local quotes for accurate pricing.