Stone Calculator
Stone sells by the cubic yard or by the ton, but your project is measured in square feet and depth. This calculator bridges that gap — converting your coverage area into cubic yards, tons, and total cost across 6 common stone types.
Quick Reference
Stone Types Compared
Different stone types serve different purposes. Here is a comparison to help you choose the right one for your project:
| Type | Weight (lbs/ft³) | Tons/Yard³ | Best For | Typical Price/yd³ |
|---|---|---|---|---|
| Crushed Stone | 100 | 1.35 | Driveways, road base, French drains | $25-$45 |
| Pea Gravel | 100 | 1.35 | Walkways, patios, gardens, drainage | $30-$55 |
| River Rock | 93 | 1.25 | Dry creek beds, decorative borders | $50-$130 |
| Lava Rock | 50 | 0.68 | Garden beds, planters, fire pits | $50-$180 |
| Decomposed Granite | 110 | 1.49 | Walkways, rustic patios, xeriscaping | $35-$65 |
| Limestone | 100 | 1.35 | Driveways, base material, drainage | $30-$45 |
Stone Depth Guide
Depth depends on your project. Too thin and it won't provide adequate coverage. Too deep and you waste money.
| Depth | Best For | Sq Ft per Ton (Crushed Stone) |
|---|---|---|
| 2 inches | Decorative beds, ground cover | 135 sq ft |
| 3 inches | Walkways, pathways, gardens | 90 sq ft |
| 4 inches | Patios, light driveways, drainage | 68 sq ft |
| 6 inches | Heavy-duty driveways, road base | 45 sq ft |
Stone vs Mulch: Which Do You Need?
Stone and mulch serve different purposes. Here is when to use each:
Use Stone When
- Building driveways or parking areas
- Creating drainage systems
- Low-maintenance ground cover
- Fire pits and outdoor fireplaces
- Erosion control on slopes
Use Mulch When
- Mulching garden beds and trees
- Retaining soil moisture
- Suppressing weeds organically
- Adding nutrients as it decomposes
- Playground safety surfaces
How to Use This Calculator
Step 1: Choose your area shape - Rectangle for standard areas, Circle for tree wells or round features, or Total Area if you already know the square footage.
Step 2: Enter dimensions. For rectangle, enter length and width. For circle, enter diameter. For total area, enter square footage directly.
Step 3: Set depth using the preset buttons (2"-6") or enter a custom value.
Step 4: Select stone type and enter pricing. The calculator shows cost per cubic yard and per ton.
Step 5: Results show instantly - cubic yards, weight in tons, coverage, and total cost breakdown.
Stone Formula
The calculator converts your project dimensions into stone volume and cost:
- Rectangle: Area = Length x Width
- Circle: Area = Pi x (Diameter / 2)²
- Volume (ft³) = Area (ft²) x (Depth in inches / 12)
- Volume (yd³) = Volume (ft³) / 27
- Weight (lbs) = Volume (ft³) x Density (varies by type)
- Tons = Weight (lbs) / 2,000
- Cost (yd³) = Volume (yd³) x Price per Cubic Yard
- Cost (ton) = Tons x Price per Ton
Density varies by stone type. Lava rock is the lightest at 50 lbs/ft³, while decomposed granite is the densest at 110 lbs/ft³. The stone type dropdown adjusts the density automatically.
Worked Example: 12x10 Walkway
Let us calculate stone for a 12 ft x 10 ft walkway at 3 inches deep using pea gravel (100 lb/ft³) with 10% waste.
Step 1: Calculate volume:
Volume = 120 x (3 / 12) = 30 ft³
Cubic Yards = 30 / 27 = 1.11 yd³
Step 2: Calculate weight:
Tons = 3,000 / 2,000 = 1.5 tons
Step 3: Calculate cost at $45/yd³:
Cost = 1.22 x $45 = $54.90
Total: 1.22 cubic yards of pea gravel at $54.90. Use the calculator above to model your own project.
Tips and Common Mistakes
Best Practices
- Use landscape fabric - Prevents weeds and stops stone from sinking into soil.
- Order 10% extra - Accounts for uneven ground, waste, and settling.
- Compact for driveways - Use angular stone that locks together for vehicle traffic.
- Consider drainage - Rounded stone like river rock drains better than angular stone.
- Match stone to project - Pea gravel for walkways, crushed stone for driveways, lava rock for beds.
Avoid This
- Using rounded stone on driveways: It shifts under vehicle weight and doesn't compact.
- Going too thin: Less than 2 inches won't provide adequate coverage or weed suppression.
- Ignoring compaction: Angular materials like crushed stone compact 15-30%, order extra.
- Skipping fabric: Without it, stone sinks into soil and weeds grow through.
- Ordering too little: Running out mid-project means a second delivery fee.
Frequently Asked Questions
Multiply your cubic yards by the stone's density. Crushed stone weighs about 1.35 tons per cubic yard (100 lbs/ft³). River rock weighs about 1.25 tons per cubic yard (93 lbs/ft³). Use the calculator above for exact numbers.
Stone costs $25-$180 per cubic yard in 2026. Crushed stone runs $25-$45, pea gravel costs $30-$55, river rock is $50-$130, and lava rock reaches $50-$180 per cubic yard.
Weight varies by stone type. Crushed stone weighs about 2,700 lbs per cubic yard (100 lbs/ft³). River rock weighs about 2,500 lbs per cubic yard (93 lbs/ft³). Lava rock is much lighter at 1,350 lbs per cubic yard (50 lbs/ft³).
Crushed stone (#57 or road base) is best for driveways. It compacts into a stable surface and drains well. Pea gravel is too loose for vehicle traffic. Use 4-6 inches of crushed stone for a durable driveway.
Use 2 inches for decorative beds and ground cover, 3 inches for walkways and pathways, 4 inches for patios and light driveways, and 6+ inches for heavy-duty driveways and drainage.
Yes, landscape fabric is strongly recommended. It prevents weeds, stops stone from sinking into soil, and makes future removal easier. Overlap edges by 6-12 inches for best results.