Quick lookup
Gravel needed for common driveways and paths (3 inches deep)
Standard 3 inch depth for paths, walkways, and decorative beds. Driveways usually need 4-6 inches total (2-3 inch sub-base plus 2-3 inch top layer). Weight assumes crushed stone at 2,700 lb / cu yard.
| Area | Sq ft | Cu yards | Cu feet | Weight (tons) | Est. cost |
|---|---|---|---|---|---|
| 3 × 20 ft path | 60 | 0.6 | 15 | 0.8 | $30 |
| 4 × 30 ft walkway | 120 | 1.1 | 30 | 1.5 | $55 |
| 10 × 10 ft pad | 100 | 0.9 | 25 | 1.2 | $45 |
| 10 × 20 ft (small drive) | 200 | 1.9 | 50 | 2.5 | $90 |
| 12 × 40 ft (1 car drive) | 480 | 4.4 | 120 | 6.0 | $220 |
| 20 × 40 ft (2 car drive) | 800 | 7.4 | 200 | 10.0 | $370 |
| 20 × 60 ft (long drive) | 1,200 | 11.1 | 300 | 15.0 | $555 |
| 12 ft diameter fire pit ring | 113 | 1.0 | 28 | 1.4 | $50 |
For driveways double these numbers (use 6 inch total depth). 1 ton covers about 75 sq ft at 3 inches deep. Compact in 2 inch lifts with a plate compactor for best results.
Quick answer
How much gravel do I need?
Gravel math is simple in theory: area × depth ÷ 27 = cubic yards. In practice you also need to know tons because gravel yards usually price by the ton or yard, depending on the stone. Different stone types weigh different amounts. Crushed stone is roughly 2,700 pounds per cubic yard. River rock can be 2,800-2,900. Decomposed granite is lighter at 2,400. Our calculator does all of this for you with accurate density factors per stone type.
The math
The formula explained
Step 1: Calculate area
Rectangle: length × width. Circle: π × radius². For irregular shapes split into rectangles.
Step 2: Convert depth to feet
Depth is usually given in inches. Divide by 12 to get feet. 3 inches = 0.25 ft.
Step 3: Multiply for cubic feet
volume = area × depth. A 20 × 10 ft area at 3 in deep is 20 × 10 × 0.25 = 50 cu ft.
Step 4: Convert to cubic yards and tons
Divide cu ft by 27 for cubic yards. Multiply cu ft by density (lb/cu ft) and divide by 2000 for tons.
Choose your stone
Stone types and their uses
| Type | Best for | |
|---|---|---|
| Pea gravel (3/8") | $40–60/yd | Paths, play areas, decorative beds. Smooth, no sharp edges. |
| Crushed stone #57 (3/4") | $35–50/yd | Driveway base, drainage, French drains. Compacts well. |
| River rock (1-3") | $50–80/yd | Decorative landscaping, dry creek beds. Heavy, doesn't move. |
| Decomposed granite | $40–70/yd | Paths, patios. Compacts to firm surface. |
| Limestone (3/4") | $30–45/yd | Most common all-purpose base material. |
| Marble chips | $70–100/yd | Decorative only. Bright white reflects heat. |
How thick?
Depth guide by use
- 1-2 in — Top dressing on existing gravel, decorative paths
- 2-3 in — Garden beds, drainage, around plants
- 3-4 in — Walking paths, dog runs
- 4-6 in — Driveway base (with proper sub-base)
- 6-12 in — Heavy traffic driveways, French drain trenches
Use cases
Common projects
Driveway (40' × 12' × 6")
8.9 cu yd. About 12 tons. Order 9 cu yd to be safe.
Pea gravel patio (12' × 10' × 3")
1.1 cu yd. About 1.5 tons. Bagged makes sense here.
French drain (50 ft × 1 ft × 1 ft)
1.85 cu yd. About 2.5 tons.
Dog run (15' × 10' × 4")
1.9 cu yd. Order 2 cu yd.
Decorative bed around foundation
30 ft × 4 ft × 3" = 1.1 cu yd of river rock or marble chips.
Walking path (50' × 4' × 3")
1.85 cu yd of pea gravel or decomposed granite.
Buying and laying gravel
Pro tips
- Most yards have a 1 cu yd minimum for delivery. Pickup loose by the half-yard.
- Bagged gravel costs 2-3x more per yard but works for projects under 0.5 cu yd.
- Always lay landscape fabric underneath. Stops weeds and keeps gravel from sinking into soil.
- For driveways: 4 in of #2 stone (bigger) as base, then 2 in of #57 (smaller) on top. Compact between layers.
- Edge gravel beds with stone or metal edging — keeps gravel where you want it.
- Plan for 5-10% loss to settling over the first 6 months.
Delivery is usually worth it
Related calculators
Gravel is rarely used alone. Add concrete on top, pavers around the edge, or mulch in the planting beds.
Last reviewed: · Methodology based on US building code standards, contractor pricing surveys, and manufacturer specifications.