Gravel quantity starts as volume and usually gets ordered by weight. This calculator turns length, width, and depth into cubic yards, then multiplies by 1.4 tons per cubic yard. That density factor is a planning conversion, not a price. For more contractor tools, use the BuilderBuzz calculator hub.
Gravel Calculator: Tons From Area, Depth, And Density
Calculate gravel tons from length, width, depth, and a 1.4 tons-per-cubic-yard density factor.
Gravel tonnage calculator
Enter area and depth. The calculator returns cubic yards and estimated tons using 1.4 tons per cubic yard.
Volume3.7 cu yd
Crushed stone5.2 tonsloose; add 20-30% for compaction
Estimates for planning only. Check the result against your plans and a supplier quote before you order.
How To Use The Tonnage
Use the tonnage to check the order, then confirm the supplier's material-specific density and ordering unit. Washed stone, crusher run, pea gravel, and recycled aggregate do not all compact or weigh the same. The calculator makes the conversion visible so the supplier conversation starts from a clear takeoff.
Sources Verified
Sources verified: June 29, 2026. This calculator uses dimensional volume math and a stated density factor only. It does not include delivered gravel prices, trucking, taxes, or regional assumptions.
How the Gravel Math Works
The whole calculation runs on one equation, and it pays to understand it instead of trusting a black box. Take your length, width, and depth, and get all three into feet first. Depth is the one that trips people, because gravel jobs get spec'd in inches. Four inches is 0.333 feet, six inches is 0.5 feet. Multiply the three numbers together and you have cubic feet. Divide by 27, because there are 27 cubic feet in a cubic yard, and now you have your volume in yards. That part is exact geometry. Nothing fuzzy about it. The next step is where judgment enters. Suppliers usually quote crushed stone by the ton, not the yard, so you convert using roughly 1.4 tons per cubic yard for most crushed stone. That factor is an average. Washed stone, crusher run, pea gravel, and recycled aggregate all weigh a little differently, and wet material weighs more than dry. So the yard number is solid and the ton number is a planning estimate. The reason this matters: some pits sell by the yard and some by the ton, and you have to know which one the quote is in before you compare two of them or you will be off by 40 percent.
A Worked Example
Say I am laying base for a driveway that runs 40 feet long and 12 feet wide, and I want 4 inches of crushed stone under it. First the depth: 4 inches divided by 12 is 0.333 feet. Now the volume in cubic feet: 12 times 40 times 0.333 comes out to about 160 cubic feet. Divide that by 27 to get cubic yards, and I land near 5.9 yards. If my supplier sells by the yard, that is most of my answer right there. To get tons, I multiply 5.9 yards by the 1.4 factor, which gives me roughly 8.3 tons of crushed stone. That is the loose, uncompacted number. It is what the truck dumps, not what stays in the ground after I roll it. So I do not order 8.3 tons and call it done. I treat 8.3 as the floor and add for compaction and for the edges I never measure cleanly. On a job this size I would round up and order around 10 tons, then keep the receipt so I know my real coverage for the next driveway. The math gives me a defensible starting number. The rounding keeps me from making a second trip.
Compaction, Tonnage, and Ordering
The calculator gives you loose volume, and loose volume is not what ends up compacted in the ground. Base rock and crusher run pack down 20 to 30 percent once you roll them, so if you order for the loose depth you come up short on the finished depth every time. The fix is to calculate for the compacted depth you actually want and then add a margin on top, not order the bare number and hope. The second trap is the ton-versus-yard confusion. A yard of crushed stone is about 1.4 tons, so the two units are not interchangeable, and pricing a yard against a ton like they are the same will blow your estimate. Confirm which unit the quote is in before you sign anything. On the ordering side, buy full truckloads when you can. A tandem dump hauls roughly 15 to 20 tons, and you pay the driver and the fuel whether the bed is full or half empty, so partial loads waste money. And source from the nearest pit that carries your spec, because freight dominates delivered cost. The rock is cheap and heavy, so the haul distance sets your price more than the material ever will.
Frequently Asked Questions
What is the gravel calculator formula? Tons = length in feet * width in feet * (depth in inches / 12) / 27 * 1.4.
Why multiply by 1.4? This calculator uses 1.4 tons per cubic yard as the gravel density conversion.
Does every gravel type weigh the same? No. Confirm the supplier's density for the exact material you are ordering.
Does this calculator price gravel? No. It calculates estimated tons only.
Should I add waste? Add a separate cushion when the job has irregular edges, soft spots, compaction loss, or grade corrections.
How do I convert gravel depth in inches to feet for the formula? Divide the inches by 12. Four inches is 0.333 feet, six inches is 0.5 feet. Get length, width, and depth all into feet, multiply them for cubic feet, then divide by 27 for cubic yards.
How much extra gravel should I order for compaction? Base rock and crusher run compact about 20 to 30 percent when you roll them, so order for the compacted depth you want and add a margin on top. The loose tonnage the calculator returns is what the truck dumps, not what stays in the ground.