Gravel Calculator
Calculate volume first, then convert to tons using the material density. Customize the density instead of relying on a one-size-fits-all assumption.
Calculate your estimate
How much gravel do I need?
Answer first: multiply length × width × depth to get volume, convert cubic feet to cubic yards, then multiply by material density to estimate tons. This calculator can add a percentage for compaction, grade variation or ordering buffer.
Density matters
Different materials can have meaningfully different weights per cubic yard. Pea gravel, crushed stone, road base and river rock are not interchangeable for tonnage estimates. Use a supplier-provided density whenever possible.
Driveway planning
A real driveway may require multiple layers, such as compacted sub-base plus a finish layer. Calculate each material layer separately instead of using one total depth.
How the gravel estimate is calculated
First convert depth from inches to feet, then calculate cubic feet:
Length × width × depth in feet = cubic feet
Divide by 27 for cubic yards, apply the waste allowance, then multiply by the density you entered to estimate tons. Density varies by aggregate type and moisture, so supplier data should replace the default when available.
Worked example: 40 × 12 ft driveway area
That is about 5.93 yd³ before waste.
Use the supplier’s actual density and order increment before purchasing.
What can change the real order
Compaction, subgrade variation, crown, edge taper, material density and supplier truck/load sizes can all move the final quantity. The calculator is best used to size the project and compare supplier quotes, not as a substitute for site preparation advice.
Frequently asked questions
How many cubic feet are in one cubic yard?
One cubic yard equals 27 cubic feet.
Why does the calculator ask for density?
Suppliers often sell aggregate by weight. Density converts estimated volume into approximate tons.
Should I add extra gravel?
A buffer can help account for compaction, uneven grade and measurement error, but final ordering should follow site conditions and supplier advice.