Sand and Gravel Calculator: How Much You Need

This sand and gravel calculator works out the volume and weight of aggregate you need for a project. You enter the length, width, and depth of the area to fill, choose the material type, and it returns the volume in cubic feet or cubic meters plus the estimated weight in pounds or tons. It uses the standard formula for a rectangular prism and typical bulk densities for common aggregates.

Formula

The calculator uses the basic volume formula for a rectangular space:

Volume = Length × Width × Depth

Then it converts the volume to weight using the material’s bulk density:

Weight = Volume × Density

Where:

• Length and Width are in feet (ft) or meters (m).
• Depth is in inches (in) or centimeters (cm) – the calculator converts it to feet or meters.
• Volume is in cubic feet (ft³) or cubic meters (m³).
• Density is the material’s weight per unit volume – typically 100 lb/ft³ for sand, 110 lb/ft³ for gravel, and 95 lb/ft³ for crushed stone.

For example, a 10 ft × 5 ft area with a 4-inch depth gives a volume of 10 × 5 × (4/12) = 16.67 ft³. Multiply by 100 lb/ft³ for sand gives 1,667 lb, or about 0.83 tons.

Worked Example

Let’s use the default values from the calculator: length = 10 ft, width = 5 ft, depth = 4 in, material = sand (density 100 lb/ft³).

1. Convert depth to feet: 4 in ÷ 12 = 0.333 ft.
2. Calculate volume: 10 × 5 × 0.333 = 16.67 ft³.
3. Convert to cubic yards: 16.67 ÷ 27 = 0.62 yd³.
4. Calculate weight: 16.67 × 100 = 1,667 lb.
5. Convert to tons: 1,667 ÷ 2,000 = 0.83 tons.

The calculator shows 16.67 ft³, 0.62 yd³, 1,667 lb, and 0.83 tons – matching the manual calculation.

When to Use This Calculator

Use this tool for any project that requires filling a rectangular space with a loose aggregate. Common situations include:

• Laying a paver base – typically 4–6 inches of gravel under pavers.
• Filling a sandbox – usually 6–12 inches of play sand.
• Creating a gravel path or driveway – often 4–8 inches of crushed stone.
• Backfilling a trench or foundation – depth varies by purpose.

For irregular shapes, break the area into rectangles, calculate each, and sum the volumes. For circular areas, use a separate formula (π × radius² × depth).

How to Read the Results

The volume tells you how much space the material will occupy. The weight tells you how much it will weigh, which matters for transport and structural support. For example, a cubic yard of sand weighs about 2,700 lb (1.35 tons), while a cubic yard of gravel weighs about 2,970 lb (1.48 tons).

When ordering, suppliers usually sell by the cubic yard (for bulk) or by the ton (for truckloads). A typical dump truck holds 10–14 cubic yards. If you’re buying bagged material, note that bags are sold by weight (e.g., 50 lb bags), so divide the total weight by the bag weight to get the number of bags.

Common Mistakes and How to Avoid Them

One frequent error is mixing units – for example, entering depth in inches but length in feet without converting. Always convert all measurements to the same unit before calculating. Another mistake is forgetting to account for compaction. When you spread and compact gravel or sand, it settles and loses volume – typically 10–20% for gravel. Order 10–15% extra to compensate.

Also, the density values used here are averages. Actual density depends on moisture content and particle size. Wet sand is heavier than dry sand, and fine gravel may pack differently than coarse. If you need precise weight, ask your supplier for the exact bulk density of the material.

Material Comparison: Sand vs. Gravel vs. Crushed Stone

Each material has different uses and densities:

• Sand – fine particles, used for bedding under pavers, sandboxes, and mortar. Density ~100 lb/ft³.
• Gravel – rounded or angular pebbles, used for drainage, driveways, and concrete aggregate. Density ~110 lb/ft³.
• Crushed stone – angular rock fragments, used for base layers and railroad ballast. Density ~95 lb/ft³.

For the same volume, gravel weighs more than sand, so it will require more tons. However, gravel provides better drainage and stability for load-bearing applications.

Cost and Ordering Considerations

This calculator gives you the quantity, not the price. Prices vary by region, availability, and delivery fees. As a rough guide, bulk sand costs $15–$30 per ton, gravel $20–$35 per ton, and crushed stone $25–$40 per ton, but these are just estimates – check local suppliers for current rates.

When ordering, you’ll need to know whether the supplier charges by the ton or by the cubic yard. If they charge by the ton, use the weight output. If they charge by the cubic yard, use the volume output. Always confirm the unit of measure before placing an order.

Safety and Accuracy Tips

When working with heavy aggregates, follow basic safety practices:

• Wear gloves and eye protection when handling or spreading material.
• Use a wheelbarrow or shovel for moving – avoid lifting too much at once.
• If you’re building a structure that supports weight (like a driveway), consult a professional engineer for load requirements.
• For large projects, order a little extra to cover spillage and compaction – 10% is a safe margin.

The calculator assumes a flat, level surface. If your area is sloped, the depth will vary – measure at several points and use the average depth for a rough estimate. For more accuracy, break the area into smaller rectangles with consistent depths.

Frequently Asked Questions

How many cubic feet are in a ton of sand?

Using a density of 100 lb/ft³, one ton (2,000 lb) of sand equals 2,000 ÷ 100 = 20 cubic feet. For gravel at 110 lb/ft³, one ton equals about 18.2 cubic feet. These are approximate – actual values depend on moisture and compaction.

How do I calculate gravel for a circular area?

Use the formula: volume = π × radius² × depth. For example, a 10-ft diameter circle (radius 5 ft) with 4 inches of gravel: π × 25 × (4/12) = 26.18 ft³, or about 0.97 yd³.

Should I order more than the calculator says?

Yes, it’s wise to order 10–15% extra. This accounts for compaction, spillage, and uneven ground. If you’re laying a paver base, the material will settle when compacted, so extra is essential.

Can I use this calculator for sand in a sandbox?

Yes. Enter the length, width, and desired depth of the sandbox. For a typical 4×4 ft sandbox with 6 inches of sand, you’d need 8 ft³, or about 0.3 yd³, which is roughly 800 lb of sand.

What is the difference between cubic yards and tons?

Cubic yards measure volume (space), while tons measure weight. The conversion depends on the material’s density. For sand, 1 cubic yard ≈ 1.35 tons; for gravel, ≈ 1.48 tons. Use the calculator’s weight output for tonnage.

How deep should gravel be for a driveway?

For a residential driveway, a common recommendation is 4–6 inches of compacted gravel. For heavy vehicles, go deeper – 8–12 inches. Always compact in layers (e.g., 4 inches at a time) for stability.

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in l | Length | ft | 10 | 0
in w | Width | ft | 5 | 0
in d | Depth | in | 4 | 0
sel mat | Material | Sand=100, Gravel=110, Crushed Stone=95
out vol_ft | Volume | cu ft | l * w * (d / 12) | 2
out vol_yd | Volume | cu yd | (l * w * (d / 12)) / 27 | 2
out weight_lb | Weight | lb | (l * w * (d / 12)) * mat | 0
out weight_t | Weight | tons | ((l * w * (d / 12)) * mat) / 2000 | 2