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Gravel Calculator

Enter your project dimensions and gravel type. Get cubic yards, cubic feet, and tons instantly.

Gravel Calculator
✓ Your estimate
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Cubic Yards
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Cubic Feet
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Tons
⚠ Add 10-15% for compaction, uneven ground, and spillage. Confirm quantities with your supplier before ordering.

What the Result Means

Gravel is sold by the cubic yard for bulk delivery and by the ton at most aggregate suppliers. One cubic yard equals 27 cubic feet. For smaller quantities, some suppliers offer bags, but bulk delivery is almost always cheaper for anything over half a yard.

If you are using gravel as a base layer for a patio or paver installation, see the paver calculator for paver count and sand bed estimates. If you are also pouring a concrete slab nearby, use the concrete slab calculator for those quantities. All outdoor material tools are listed at the outdoor calculators page. For retaining wall base and drainage gravel specifically, see the retaining wall block calculator which estimates base gravel alongside block counts.

Common Gravel Types

Pea Gravel
Small, smooth, rounded stones. Best for walkways, playgrounds, and drainage. Not ideal for driveways -- it shifts underfoot.
Crushed Stone (#57)
Angular, interlocking pieces. Excellent for driveways and base layers. Good drainage. Most common contractor choice.
Road Base / Caliche
Mixed crushed stone and fines that compact firmly. Best base layer for driveways and patios. Locks in place over time.
River Rock
Smooth, rounded stones. Primarily decorative. Good for landscaping borders, dry creek beds, and garden beds.

Why Does Gravel Density Vary?

Gravel density depends on particle size, shape, and moisture content. Angular, tightly-packed crushed stone is denser than smooth, loosely-packed pea gravel. Wet gravel is heavier than dry. When ordering, ask your supplier for the exact density of the material you are purchasing so your ton estimate is accurate.

How the Calculation Works

Cubic Feet = Length x Width x (Depth / 12)
Cubic Yards = Cubic Feet / 27
Tons = Cubic Yards x Density (tons per yd)
Density varies: pea gravel ~1.4 t/yd | road base ~1.25 t/yd | dense-grade ~1.5 t/yd

Worked Example

Example: 30 ft x 12 ft driveway, 4 inches of crushed stone

1
Convert depth: 4 / 12 = 0.333 feet
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Cubic feet: 30 x 12 x 0.333 = 120 cubic feet
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Cubic yards: 120 / 27 = 4.44 cubic yards
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Tons: 4.44 x 1.35 = 5.99 tons
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Add 15% compaction buffer: order 5.1 yards / 6.9 tons

Ordering Notes

Before You Order

  • Driveways: 4-6 inches of compacted base layer is standard; 2-3 inch top coat on top
  • Walkways and patios: 2-4 inches is typical
  • Compaction factor: loose gravel compacts 10-15% -- always order extra
  • Delivery minimums: most suppliers require 1 ton minimum; short-load fees common under 3 tons
  • Moisture: wet gravel is heavier per yard -- delivery weight may exceed your estimate

Assumptions Used by This Calculator

  • Length and width are entered in feet; depth is entered in inches and divided by 12.
  • Volume is calculated as length x width x depth (in feet).
  • Cubic feet are divided by 27 to get cubic yards.
  • Tons are estimated by multiplying cubic yards by the selected gravel density.
  • Density values are averages; actual weight varies by moisture content, compaction, and supplier material.
  • Compaction loss (10-15%) is not included -- add it manually before ordering.

Frequently Asked Questions

How many tons of gravel are in a cubic yard?
It depends on the gravel type. Pea gravel and #57 crushed stone are about 1.4 tons per cubic yard. Road base is around 1.25 tons per yard. Dense-grade aggregate is closer to 1.5 tons per yard. Ask your supplier for the exact density of their material.
How deep should gravel be for a driveway?
A standard residential gravel driveway needs 4-6 inches of compacted base material (road base or dense-grade aggregate) plus a 2-3 inch top coat. Heavy vehicle traffic warrants the deeper end of that range.
What is the difference between pea gravel, crushed stone, and road base?
Pea gravel is smooth and rounded -- good for drainage and decorative use but not for driveways. Crushed stone (#57) is angular and interlocking -- the standard driveway top coat. Road base is a blend of crushed stone and fine particles that compacts firmly -- the best base layer for driveways and patios.
How much gravel do I need for a 10x20 driveway?
At 4 inches deep, a 10x20 driveway needs about 2.47 cubic yards or roughly 3.5 tons of crushed stone. Add 15% for compaction and order about 2.84 cubic yards or 4 tons. Use the calculator above for your exact dimensions.
Why does gravel density vary?
Gravel density depends on particle size, shape, and moisture content. Angular, tightly-packed crushed stone is denser than smooth, loosely-packed pea gravel. Wet gravel is heavier than dry. Always confirm density with your supplier before placing a large order.
How much does a cubic yard of gravel cover?
At 2 inches deep, 1 cubic yard covers about 162 sq ft. At 3 inches deep, about 108 sq ft. At 4 inches deep, about 81 sq ft. Use the calculator above for your exact dimensions and depth.
Do I need landscape fabric under gravel?
For decorative gravel in garden beds, landscape fabric helps suppress weeds. For driveways and hardscape base layers, skip the fabric -- it can interfere with compaction and drainage. For walkways, a weed barrier is optional but helps with long-term maintenance.
Disclaimer: This calculator provides estimates only. Actual quantities depend on compaction rate, site conditions, and material density. Verify all quantities with your gravel supplier before ordering. See all outdoor material calculators.