How much stone or gravel do I need?
Enter the size and depth of your area and pick a material category and material. See how many tons and cubic yards of stone to order, and the cost.
- Stone to order
- 1.44 tons
100 ft² of stone at 3 in deep needs 1.44 tons with the waste allowance.
- Metric tonnes
- 1.31 t
- Volume to order
- 1.02 yd³
- Area
- 100 ft²
- Coverage per ton
- 76.2 ft²
- Density used
- 105 lb/ft³
Stone to order: 1.44 tons. 100 ft² of stone at 3 in deep needs 1.44 tons with the waste allowance.
How to calculate
Computes the tons and cubic yards of gravel, crushed stone or base material for an area at a chosen depth, with a waste allowance, and the cost per ton.
Example with the default inputs (Area shape Rectangle, Length (diameter for a circle, base for a triangle) 10 ft, Width (height for a triangle) 10 ft, Depth 3 in, Material category Decorative gravel, Material Pea gravel, Waste allowance 10%): 100 ft² of stone at 3 in deep needs 1.44 tons with the waste allowance.
Method: tons = area × depth × (1 + waste ÷ 100) × density ÷ 2,000 lb
- Rectangle: length × width. Circle: π × diameter² ÷ 4. Triangle: base × height ÷ 2.
- The density is the typical loose, dry bulk density of the chosen material unless you type your own. Wet or compacted stone weighs more.
- Tons are US short tons of 2,000 lb; tonnes are metric tonnes of 1,000 kg.
- Coverage per ton is 2,000 lb ÷ (depth × density), before the waste allowance.
Worked examples
Each example is checked against the calculator on every build.
- Area shape Rectangle, Length (diameter for a circle, base for a triangle) 10 ft, Width (height for a triangle) 10 ft, Depth 3 in, Material category Decorative gravel, Material Pea gravel, Waste allowance 10%, Price per ton $35.00 gives Stone to order 1.44 tons, Estimated cost $50.53, Coverage per ton 76.2 ft².Source: Engineering ToolBox, Dirt and Mud - Densities (gravel, dry 105 lb/ft³). https://www.engineeringtoolbox.com/dirt-mud-densities-d_1727.html
- Area shape Rectangle, Length (diameter for a circle, base for a triangle) 20 ft, Width (height for a triangle) 10 ft, Depth 4 in, Material category Crushed stone, Material Crushed limestone #57, Waste allowance 0% gives Stone to order 3 tons, Volume to order 2.47 yd³.Source: Engineering ToolBox, Dirt and Mud - Densities (gravel, dry 105 lb/ft³). https://www.engineeringtoolbox.com/dirt-mud-densities-d_1727.html
- Area shape Circle, Length (diameter for a circle, base for a triangle) 10 ft, Depth 2 in, Material category Decorative gravel, Material Lava rock, Waste allowance 0% gives Area 78.5 ft², Stone to order 0.28 tons.Source: Engineering ToolBox, Dirt and Mud - Densities (gravel, dry 105 lb/ft³). https://www.engineeringtoolbox.com/dirt-mud-densities-d_1727.html
- Area shape Triangle, Length (diameter for a circle, base for a triangle) 13.12 ft, Width (height for a triangle) 9.843 ft, Depth 3.937 in, Material category Base material, Material Road base (crusher run), Material density 112.4 lb/ft³, Waste allowance 5% gives Area 64.6 ft², Metric tonnes 1.13 t.Source: Engineering ToolBox, Dirt and Mud - Densities (gravel, dry 105 lb/ft³). https://www.engineeringtoolbox.com/dirt-mud-densities-d_1727.html
How it works
- Area. Rectangle: length × width. Circle: π × diameter² ÷ 4 (enter the diameter as the length). Triangle: base × height ÷ 2 (enter the base as the length and the height as the width).
- Volume to order = area × depth × (1 + waste ÷ 100).
- Weight = volume to order × density. The weight in US tons is pounds ÷ 2,000; metric tonnes are kilograms ÷ 1,000.
- Coverage per ton = 2,000 lb ÷ (depth in feet × density in lb/ft³). It is the area one ton covers at your depth, before the waste allowance.
- Cost = weight in US tons × price per ton. It is shown only when you enter a price.
Pick a material category first, then a material from that category. The calculator uses the material's typical density unless you type your own.
Typical densities
These are loose, dry bulk densities. Each is the published value or the middle of the published range. Wet or compacted stone weighs more, so a weight from your supplier is better when you have one.
| Category | Material | Density used | Published value |
|---|---|---|---|
| Decorative gravel | Pea gravel | 105 lb/ft³ | gravel, dry, 105 lb/ft³ |
| Decorative gravel | River rock (1-2 inch) | 105 lb/ft³ | gravel, dry, 105 lb/ft³ |
| Decorative gravel | Decomposed granite | 108 lb/ft³ | sand with gravel, dry, 108 lb/ft³ |
| Decorative gravel | Lava rock | 42.5 lb/ft³ | pumice, 40 to 45 lb/ft³ |
| Crushed stone | Crushed limestone #57 | 90 lb/ft³ | limestone, crushed, 85 to 95 lb/ft³ |
| Crushed stone | Crushed sandstone | 87.5 lb/ft³ | sandstone, crushed, 80 to 95 lb/ft³ |
| Base material | Road base (crusher run) | 108 lb/ft³ | sand with gravel, dry, 108 lb/ft³ |
| Base material | Sand (dry) | 90 lb/ft³ | sand, dry, 80 to 100 lb/ft³ |
Sources: Engineering ToolBox, Densities of common Products and Dirt and Mud - Densities (retrieved September 27, 2026). 1 lb/ft³ = 16.0185 kg/m³.
Worked examples by hand
A 10 ft × 10 ft bed of pea gravel, 3 in deep, 10% extra, at $35 a ton. 100 × 0.25 × 1.1 = 27.5 ft³. 27.5 × 105 = 2,887.5 lb = 1.44 tons. The cost is 1.444 × $35 = $50.53. One ton covers 2,000 ÷ (0.25 × 105) = 76.2 ft² at this depth.
A 20 ft × 10 ft driveway of crushed limestone #57, 4 in deep, no extra. 20 × 10 × 4/12 = 66.67 ft³ = 2.47 yd³. 66.67 × 90 = 6,000 lb = 3 tons.
A circle of lava rock 10 ft across, 2 in deep, no extra. π × 10² ÷ 4 = 78.54 ft². 78.54 × 2/12 = 13.09 ft³. 13.09 × 42.5 = 556.3 lb (0.28 tons).
A triangle of road base with a 4 m base and 3 m height, 10 cm deep, 5% extra, at 1,800 kg/m³. 4 × 3 ÷ 2 = 6 m². 6 × 0.1 × 1.05 = 0.63 m³. 0.63 × 1,800 = 1,134 kg (1.13 tonnes).
Other questions people ask
How does the stone calculator work?
The stone calculator works out the area of your project space, multiplies it by the depth to get the volume, adds a waste allowance, and converts the volume to weight with the density of the material you choose. For example, a 10 ft × 10 ft bed of pea gravel 3 inches deep with 10% extra is 27.5 cubic feet, which at 105 lb per cubic foot is 2,887.5 lb, or 1.44 tons.
What types of projects can I calculate with this tool?
This calculator handles a wide range of landscaping and construction projects including ground cover and decorative beds, pathways and patios, driveways, paver bases, and other areas filled with loose stone. Pick the depth your project needs.
How accurate are the calculations?
The volume is exact for the dimensions you enter. The weight depends on the density, which varies with the stone, its size, its moisture, and how tightly it is packed. The calculator uses typical loose, dry densities; for large orders, ask your supplier for the weight per cubic yard of their material and type it in.
What is a waste factor and why is it important?
A waste factor accounts for material that gets lost during installation due to spillage, uneven ground, cutting, and shaping. Many professionals add about 10% extra material to avoid running short. The calculator adds this allowance to the volume and weight to order.
How do I choose the right material for my project?
Material selection depends on your project type, budget, and aesthetic preferences. Decorative gravels like pea gravel and river rock are common for pathways and garden beds. Crushed stone works well for driveways and bases. Base materials like road base provide foundation support. Consider drainage needs, traffic load, and maintenance when making your selection.
What's the difference between bulk and bagged materials?
Bulk materials are sold by the ton or cubic yard and delivered in large quantities, making them more cost-effective for larger projects. Bagged materials come in smaller quantities (typically 0.5 cubic feet) and are convenient for smaller projects or areas with limited access.
How do I measure irregularly shaped areas?
For irregular shapes, break your area into smaller, manageable shapes like rectangles, triangles, or circles. Calculate each section separately and add the results together.
What depth should I use for different project types?
Common depths are 2-3 inches for pathways, at least 3 inches for decorative beds, and 4-6 inches for driveways and paver bases. Check the product and local guidance for your project.
How do I convert between different units of measurement?
You can enter each dimension in feet, inches, yards, meters, or centimeters, and pick the unit next to each box. The calculator converts everything exactly before it multiplies.
What is material density and why does it matter?
Material density is how much a material weighs per unit volume (typically pounds per cubic foot). Different stone types have different densities - for example, lava rock is much lighter than crushed limestone. The calculator uses the density to convert volume to weight.
Can I use this calculator for flagstone or wall stone projects?
This calculator is for loose materials like gravel, crushed stone, and aggregates. Flagstone and wall stone are usually sold by the area they cover rather than by volume, so ask your supplier for their coverage per ton.
What should I do if my calculations seem too high or low?
Double-check your measurements and ensure you're using the correct units. Check that the depth is in inches, not feet: 3 feet of gravel is twelve times as much as 3 inches. If the weight still seems unusual, compare the density with the one your supplier gives.