Gravel Calculator
Estimate gravel for driveways, paths and drainage in tons and cubic yards. Rectangular or circular areas, imperial or metric, with a stated density you can check.
How to use the gravel calculator
- Choose rectangle or circle to match the area you are covering.
- Enter length and width in feet, and depth in inches. Use 4 inches as a starting point for paths, more for driveways.
- Read tons and cubic yards. Quarries sell by the ton or the yard, so you get both.
- Add sections for L-shaped drives or several paths and total them at once.
Tons, yards and the density assumption
Gravel is priced by weight or by volume, so the useful step is converting between them. This tool figures volume as area × depth, converts to cubic yards, then multiplies by a density of 1.4 tons per cubic yard — a fair average for crushed gravel and road base. Lighter pea gravel and heavier dense-grade rock sit on either side of that, roughly 1.2 to 1.7 tons per yard.
| Material | Approx. density |
|---|---|
| Pea gravel | 1.25 tons/yd³ |
| Crushed gravel / #57 stone | 1.40 tons/yd³ |
| Crushed stone base (dense grade) | 1.55 tons/yd³ |
Getting the depth right
Skimp on depth and stone scatters and ruts; overdo it and you pay for gravel that never compacts properly. For a driveway, a compacted sub-base plus a 3 to 4 inch top layer holds up far better than one deep, loose pour. Edging — timber, steel or a paver soldier course — keeps everything where you put it.
Ordering tips
- Round up to the nearest half-ton; most yards sell in those increments.
- Ask the density of the specific product; it changes the tonnage.
- Keep the 10 percent waste factor on for spread, compaction and the odd low spot.
Frequently asked questions
How many tons of gravel do I need?
Find the volume in cubic yards (area × depth ÷ 27), then multiply by about 1.4 tons per cubic yard for typical crushed gravel. A 30 ft by 10 ft path at 4 inches deep is about 3.7 cubic yards, or roughly 5.2 tons. This calculator applies the density and a waste factor automatically.
How much gravel do I need for a driveway?
Most driveways use a 4 to 6 inch total depth, often in two layers: a coarser base and a finer top. Measure length by width, choose your depth, and read the tons. A 12 ft by 40 ft driveway at 4 inches is about 5.9 cubic yards or 8.3 tons before waste.
How many cubic yards are in a ton of gravel?
At roughly 1.4 tons per cubic yard, one ton is about 0.71 cubic yards, and one cubic yard weighs about 1.4 tons. Density varies with stone type and moisture, so treat it as a close estimate and confirm with your quarry.
What depth of gravel should I use?
Two inches suffices for a decorative top-dressing, 3 to 4 inches for walking paths, and 4 to 6 inches for driveways that carry vehicles. Deeper installs usually need a compacted sub-base and edging to keep the stone in place.
Why does the tool assume 1.4 tons per cubic yard?
That is a common average for crushed gravel and road base. Pea gravel runs a little lighter and dense crushed rock a little heavier — roughly 1.2 to 1.7 tons per cubic yard. If your supplier gives an exact density, use their figure for the order.
Tonnage is an estimate for planning only. Gravel density varies with stone type, size and moisture. Use your supplier’s stated density for the final order.