Gravel Calculator

How to Calculate Gravel

Our gravel calculator helps you estimate cubic yards and tons of gravel for paths, patios, driveways, and landscape beds. Multiply the length by the width and the depth in feet to get cubic feet, then divide by 27 for cubic yards. We add 5% waste to cover settling and uneven ground.

Choosing a Gravel Type

• Pea gravel: Small, rounded, and comfortable underfoot - best for decorative beds and walkways
• Crushed stone: Angular pieces that lock together - best for driveways and base layers
• River rock: Larger smooth stones - best for drainage and accent areas
• Decomposed granite: Fine, compactable material - best for paths and patios

Gravel Depth Guidelines

Use 2-3 inches of gravel for decorative ground cover and landscape beds, and 3 inches for most walking paths. Driveways need 4-6 inches installed in compacted layers, typically with a larger crushed stone base under a smaller top course. Deeper layers spread vehicle loads and prevent ruts.

Gravel Calculator Formula

The calculator works in feet and inches (metric entries are converted first) and uses these steps and constants:

1. Area: length × width, in square feet
2. Cubic feet: area × (depth in inches ÷ 12)
3. Cubic yards: cubic feet ÷ 27, then × 1.05 to add 5% for settling and uneven ground
4. Tons: cubic yards × the weight of the gravel in tons per cubic yard: 1.4 for pea gravel, 1.45 for crushed stone, 1.25 for river rock and 1.35 for decomposed granite
5. Bags: cubic feet × 1.05 ÷ 0.5, rounded up to whole 0.5 cu ft bags
6. Material cost: tons × $30 to $75 per ton, a 2026 national bulk range, before delivery

In one line: tons = length × width × (depth ÷ 12) ÷ 27 × 1.05 × tons per cubic yard.

Worked Example: 10 x 50 ft Gravel Driveway at 4 Inches

A 10 ft wide, 50 ft long driveway with a 4 inch layer of crushed stone:

• Area: 10 × 50 = 500 sq ft
• Volume: 500 × (4 ÷ 12) = 166.67 cu ft
• Cubic yards: 166.67 ÷ 27 = 6.17, plus 5% = 6.48 cu yd
• Tons: 6.48 × 1.45 = 9.40 tons of crushed stone
• Bags: 166.67 cu ft plus 5% = 175 cu ft, or 350 bags of 0.5 cu ft
• Material cost: 9.40 tons at $30 to $75 per ton, which the calculator rounds to $300 to $700

These are the figures the calculator shows for the same inputs. The same driveway in pea gravel takes 9.07 tons, because pea gravel weighs a little less per cubic yard. At this size, bulk delivery by the ton is far less work than 350 bags. For prices per ton by gravel type, delivery fees and installed prices, see the gravel driveway cost guide, or compare gravel with concrete, asphalt and pavers in the driveway cost guide.

Building the driveway in two layers? Run the calculator once for each layer at its own depth and add the tons together. Crusher run is not one of the calculator's gravel types; choosing crushed stone gives a close estimate for a base layer, though crusher run with fines is typically a little heavier (see the table below). For a paver patio or walkway base, the paver calculator works out the gravel base together with pavers and sand.

Gravel Weight per Cubic Yard and Coverage per Ton

A cubic yard of gravel weighs more than a ton, so a ton covers less than a cubic yard. The first four weights are the ones this calculator uses. Crusher run is not a calculator option, so its weight is a typical figure. Real weights vary with the supplier, stone size and moisture, so treat these as typical values and go by the weight on your supplier's ticket.

Coverage is the area one ton fills at each depth before the 5% waste allowance, rounded to the nearest square foot. To turn tons into cubic yards, divide by the weight per cubic yard: one ton of pea gravel is about 0.71 cubic yards.