Calculate Gravel for Driveways, Paths, and Drainage
Gravel projects fail when you order the wrong type or too little material. A driveway with insufficient depth develops ruts and potholes within months. This calculator determines how many tons or cubic yards of gravel you need based on area, depth, and gravel type-plus helps you choose the right stone for your application.
Understanding Gravel Types
Gravel isn't generic-each type serves specific purposes:
- Crushed stone (¾"): Driveways, base layers. Angular edges lock together for stability. Most common choice.
- Pea gravel (⅜"): Pathways, playgrounds, decorative areas. Smooth, rounds, comfortable to walk on barefoot but shifts under vehicle traffic.
- Crusher run (¼"-¾" mix): Best driveway base. Contains stone dust that compacts into a cement-like surface when wet and rolled.
- River rock (1-3"): Decorative landscaping, drainage. Smooth stones don't compact well for traffic areas.
- #57 stone (¾"): Drainage applications, French drains, septic systems. Large voids allow water flow.
Measuring for Gravel
1. Calculate area: Measure length × width in feet. For irregular shapes, break into rectangles or use the average width along the length.
2. Determine depth: Driveways need 4-6 inches of gravel (deeper for soft soil or heavy vehicles). Paths need 2-4 inches. Drainage layers need 6-12 inches.
3. Account for compaction: Gravel compacts 20-30% when driven on or rolled. Order 25% more than calculated volume to account for settling.
4. Convert to tons: Gravel is sold by the ton (sometimes cubic yard). Average gravel weighs 1.4-1.7 tons per cubic yard depending on type. Crushed stone is denser; pea gravel is lighter.
Installation Best Practices
Excavate to proper depth: Remove sod, roots, and soft soil. If you're adding 4 inches of gravel, excavate 6 inches to allow for compaction and base material.
Install landscape fabric: Place commercial-grade woven geotextile fabric over excavated soil before adding gravel. This prevents gravel from sinking into soft ground and weeds from growing up through the stone.
Build up in layers: For driveways, install a base layer of crusher run (3-4 inches), compact with a plate compactor or roller, then add a top layer of ¾" crushed stone (2-3 inches). Two compacted layers outlast a single thick layer.
Crown the driveway: Create a gentle peak down the center (2-3% slope) so water runs to the edges, not down the middle. Standing water erodes gravel and creates ruts.
Common Gravel Mistakes
Using the wrong stone size: Large stones (2-3") create a bumpy surface unsuitable for walking or vehicle traffic. Fine stone (#8, #9) compacts too much and becomes muddy. Stick to ¾" for most applications.
Skipping the base layer: Putting pretty pea gravel directly on dirt guarantees it will sink and disappear within a year. Always use crusher run or compacted stone dust as a base.
Not compacting: Loose gravel shifts, rutts, and spreads. Rent a plate compactor ($50-80/day) for driveways and paths. Compact in 2-inch lifts (layers) by watering lightly and running the compactor over each layer 3-4 times.
Ordering too little: Running out mid-project means additional delivery fees (often $50-150). Always round up to the next half-ton or full cubic yard.
Total Materials Needed
Enter dimensions above to see results
Pro Tips
- Driveways: 4–6" depth with compacted base
- Walkways: 2–3" depth is usually sufficient
- French drains: Fill trench with 3/4" gravel
- Gravel weighs about 1.4 tons per cubic yard (varies by type)
- Pea gravel is lighter (~1.3 tons/yd³), crushed stone heavier (~1.5 tons/yd³)
- Order 10–15% extra, gravel always seems to disappear
Frequently Asked Questions
Q: How much does gravel cost?
A: $15-50 per ton delivered depending on type and distance. Crusher run is cheapest ($15-25/ton); decorative river rock is most expensive ($40-75/ton). Delivery adds $50-150 for small loads; free delivery is common for 10+ tons.
Q: How do I keep gravel in place?
A: Install edge restraints (steel or aluminum edging, pressure-treated timbers, or Belgium blocks). Without edges, gravel migrates into lawns and planting beds. Compact thoroughly-loose gravel shifts more than compacted.
Q: Can I drive on pea gravel?
A: Not for regular vehicle traffic. Pea gravel's round shape doesn't lock together, so it shifts and creates ruts. Use ¾" crushed stone for driveways. Pea gravel is fine for decorative areas and low-traffic paths.
Q: How often does gravel need replenishment?
A: Properly installed gravel driveways need fresh stone every 3-5 years. Add 1-2 inches when ruts develop or stone becomes sparse. Paths need refreshing every 2-3 years.
Q: What's the difference between cubic yards and tons?
A: Cubic yards measure volume; tons measure weight. Gravel suppliers sell by weight (tons) but you calculate volume (cubic yards). Use conversion: 1 cubic yard ≈ 1.4 tons for most gravel types.
How to Calculate Gravel
Calculating the right amount of gravel requires a simple four-step process:
- Measure the area in feet: Length × Width. For irregular shapes, break into rectangles and add the areas.
- Determine the depth: Typical depths are:
- 2–3 inches for paths and walkways
- 4–6 inches for driveways (4" minimum; 6" for soft or high-traffic areas)
- 6–12 inches for drainage layers and French drains
- 1–2 inches for decorative landscaping
- Apply the formula: (Length ft × Width ft × Depth in) ÷ 324 = cubic yards
Example: A 12 ft × 50 ft driveway at 4" deep: (12 × 50 × 4) ÷ 324 = 7.4 cubic yards - Convert to tons (optional): Cubic yards × 1.4 = approximate tons
7.4 cubic yards × 1.4 = 10.4 tons (varies by gravel type; crushed stone is heavier, pea gravel lighter) - Add 10% for waste and compaction: Gravel settles 20–30% when compacted. Order 10–15% extra to account for settling and spillage.
Gravel Coverage Chart
Use this table to estimate coverage for different depths. These are approximate values for standard crushed stone or pea gravel.
| Depth | Coverage per Cubic Yard | Coverage per Ton |
|---|---|---|
| 1 inch | ~324 sq ft | ~232 sq ft |
| 2 inches | ~160 sq ft | ~115 sq ft |
| 3 inches | ~108 sq ft | ~77 sq ft |
| 4 inches | ~81 sq ft | ~58 sq ft |
| 6 inches | ~54 sq ft | ~38 sq ft |
| 12 inches | ~27 sq ft | ~19 sq ft |
Types of Gravel & Best Uses
Different gravel types serve specific purposes. Choose based on your project and budget:
- Crushed stone (¾"): Angular edges lock together for stability. Best for driveways and base layers. Cost: $15–30/ton. Density: ~1.5 tons/cubic yard.
- Crusher run (¼"–¾" mix): Stone dust + gravel mix that compacts into a cement-like surface when wet and rolled. Ideal for driveway base layers. Cost: $15–25/ton. Best compaction performance.
- Pea gravel (⅜"): Smooth, rounded stones. Comfortable for walking barefoot. Not suitable for driveways (shifts under vehicle weight). Best for paths, playgrounds, and decorative areas. Cost: $20–40/ton. Density: ~1.3 tons/cubic yard.
- River rock (1–3"): Large, smooth, decorative stones. Doesn't compact; shifts easily. Use for landscaping, dry creek beds, and water features only. Cost: $40–75/ton. Poor for traffic areas.
- #57 stone (¾"): Uniform size, crushed angular stone. Excellent drainage characteristics. Use for French drains, septic systems, and underground utilities. Cost: $20–35/ton.
- Jersey shore gravel: Mixed shells, sand, and small stones. Compacts well, inexpensive. Regional availability. Cost: $10–20/ton.
- Marble chips: White, decorative, expensive. Use only for high-end landscaping. Cost: $75–150/ton.
Common Gravel Projects & Calculations
Here are typical project sizes to help you estimate your needs:
Driveway Gravel (12 ft × 50 ft, 4" deep)
- Cubic yards: 7.4 yd³
- Tons: ~10.4 tons (crushed stone)
- 50 lb bags: ~400 bags
- Estimated cost: $155–310 (bulk delivery)
- Note: Use crushed stone or crusher run in 2 layers: 3" base + 1" top finish
Patio Base (10 ft × 12 ft, 4" deep)
- Cubic yards: 1.48 yd³ (round to 1.5)
- Tons: ~2.1 tons
- 50 lb bags: ~110 bags
- Estimated cost: $35–65 (bulk) or $350–450 (bags)
- Note: Crusher run compacts best for patio pavers or travertine tiles
French Drain (50 ft length, 1 ft wide, 1 ft deep)
- Cubic yards: 1.85 yd³
- Tons: ~2.6 tons (#57 stone preferred)
- Estimated cost: $40–90
- Note: Use perforated drain pipe + landscape fabric + #57 stone gravel
Pathway (40 ft × 2 ft, 2" deep)
- Cubic yards: 0.49 yd³ (round to 0.5)
- Tons: ~0.7 tons
- 50 lb bags: ~35 bags
- Estimated cost: $12–25 (bulk) or $140–210 (bags)
- Note: Pea gravel or crusher run; 2–3" is comfortable for walking
Decorative Landscaping (20 ft × 15 ft, 3" deep)
- Cubic yards: 2.78 yd³
- Tons: ~3.9 tons (pea gravel or river rock)
- Estimated cost: $65–150
- Note: River rock is more expensive but lasts longer without weeding
Tips for Ordering Gravel
- Always order 10–15% extra: Gravel settles 20–30% when compacted. A shortage mid-project means additional delivery charges ($50–150 per trip).
- Check delivery minimums: Most suppliers have a 3–5 ton minimum. Smaller projects may cost more due to delivery fees ($50–150). Ask about bulk discounts for orders over 10 tons.
- Ask about compaction rate: Ask your supplier for the material's compaction percentage. Crusher run compacts 25–35%; crushed stone compacts 15–25%; pea gravel compacts 10–15%.
- Get a quote on delivery: Delivery costs vary by distance. Some suppliers include delivery for large orders (10+ tons). Compare bulk delivery vs. bagged pricing.
- Schedule delivery for crew work: Gravel should be spread and compacted within 1–2 days of delivery. Uncompacted piles settle unevenly and can shift. Plan to rent a plate compactor if you have a large area.
- Know your vehicle capacity: A standard pickup truck holds 1.5–2 tons; a dump truck holds 10–15 tons. Multiple small pickups cost more in time/fuel than one bulk delivery.
- Ask about colors and types: Standard crushed stone is gray; decorative colors (red, brown, white) cost more. Request samples before committing to large orders.