Gravel Calculator
Plan the amount of gravel you need for driveways, paths, patios, drainage beds and other projects. Build one area or combine several sections, then see volume, approximate weight, bags and optional cost.
1. Set your project
Choose a unit system and a material preset. Preset densities are starting points; use your supplier's figure when you have it.
2. Add project areas
Use one section for a simple area. For an irregular project, split it into rectangles, circles or triangles and add each part.
3. Ordering assumptions
An allowance can cover spillage, uneven subgrade and similar field losses. It is not a universal engineering compaction factor.
Your estimate
Enter your project details and calculate to see the estimate.
Quick coverage reference
Approximate coverage area for one unit of volume at common layer depths. Actual coverage varies with material and compaction.
| Depth | Coverage per cubic yard | Coverage per cubic metre |
|---|---|---|
| 2 in / 50.8 mm | ≈ 13.5 sq yd | ≈ 19.7 sq m |
| 4 in / 101.6 mm | ≈ 6.75 sq yd | ≈ 9.84 sq m |
| 6 in / 152.4 mm | ≈ 4.5 sq yd | ≈ 6.56 sq m |
| 8 in / 203.2 mm | ≈ 3.38 sq yd | ≈ 4.92 sq m |
How the calculator works
For each area, the calculator determines surface area from the shape and multiplies it by the entered depth. Multiple sections are combined, then the optional allowance is applied to the total volume.
Weight & ordering
The selected density converts volume into an approximate weight. Order quantity is rounded according to the unit system and supplier minimum you enter.
Frequently asked questions
How do I calculate how much gravel I need?
Measure the surface area and the installed depth, calculate the volume, then use a supplier or material density to estimate weight. This calculator also lets you combine multiple areas and add an optional ordering allowance.
What density should I use?
Use the exact bulk density from your supplier or delivery paperwork when available. Presets here are planning estimates and can vary with stone type, source, moisture and compaction.
How much extra gravel should I order?
There is no single percentage that is correct for every site. Use the allowance field for spillage, uneven subgrade and similar losses, based on your project conditions or supplier advice.
Can I calculate an irregular project?
Yes. Add sections and split the project into simple shapes. The calculator sums the volumes before applying the common allowance.
Are the tons exact?
No. Your measured volume is determined by the dimensions and depth entered. Weight depends on the density assumption, so the final delivered weight may differ from the estimate.
Planning note
This tool is for planning and estimating material quantities. It does not determine an engineered base thickness or drainage design. For structural work, site-specific specifications or professional advice may be required.