Gravel Driveway Material Calculator

Gravel is measured in cubic yards and sold in tons, and the bridge between them changes with the material you buy. That single conversion is where most driveway orders go wrong — either short by a load, or over by several tons of stone you paid to haul.

This calculator takes area × depth, converts to cubic yards, adds a compaction allowance, and applies your supplier's tons-per-cubic-yard. Below the tool, every step is shown, the depth decision is broken down honestly, and the things the estimate cannot see are listed so you can adjust before the truck is loaded. If your driveway has failing sections rather than a thin surface, start at the gravel driveway hub instead — material quantity is not the fix for a drainage problem.

The division by 27 is the only step people routinely get wrong: there are 27 cubic feet in a cubic yard, and gravel volume is quoted in yards. Everything after that is a unit conversion your supplier needs in order to load a truck.

A 600 ft lane, 12 ft wide, getting a 4 in topcoat of dense-graded aggregate. Compaction allowance 10%, and the quarry quotes 1.4 tons per cubic yard for that product.

• Area: 600 × 12 = 7,200 sq ft
• Volume: 7,200 × (4 ÷ 12) = 2,400 cu ft ÷ 27 = 88.9 cubic yards
• With 10% allowance: 88.9 × 1.10 = 97.8 cubic yards
• Tons: 97.8 × 1.4 = 136.9 tons — order 137

Now change one input to see what actually drives the number. Go from 4 in to 6 in and tonnage rises to about 205 tons — a 50% increase in material for a depth change that sounds minor. Depth is the most expensive input on this page, which is why it is worth deciding deliberately rather than rounding up "to be safe."

Change tons-per-yard instead, from 1.4 to 1.6, and the same volume becomes about 156 tons. That is roughly 19 extra tons purely from a conversion factor. Getting the real figure from your supplier before ordering is a two-minute phone call that removes the largest source of error in the estimate.

• Under 3 in — a dressing, not a driveway. Fine for freshening a sound surface; it will not carry loaded trucks or fix ruts.
• 3–4 in over a solid, existing base — the normal topcoat range for a lane that still has structure underneath.
• 4–6 in — typical for residential drives being built up, usually placed and compacted in layers rather than one lift.
• Over 6 in — new construction over weak subgrade, or sections that carry heavy delivery and equipment traffic. Expensive; make sure the depth is solving a real bearing problem.

Two points that change the answer more than the number itself. First, thick single lifts do not compact through — material placed in layers with compaction between them performs better than the same tonnage dumped at once. Second, if soft spots come back every wet season, the problem is drainage or subgrade, and adding stone on top buries money rather than fixing it. Crown, ditches, and culverts come before depth.

• Your material's actual density. Tons per cubic yard varies with stone type, gradation, and how wet the stockpile is on delivery day. Wet material weighs more per yard for the same coverage.
• Subgrade losses. Over soft clay or mud, the first inches of base stone push down into the subgrade instead of building up. That material is spent but not visible, and geotextile fabric is what stops it.
• Turnouts, aprons, and parking areas. Measure and add them separately; they are often a surprising share of the total.
• Crown and shoulders. A crowned cross-section holds more material than a flat rectangle of the same nominal depth.
• Truck capacity and pricing. This page shows no load count or dollar figure, because both depend entirely on your supplier's trucks and local rates. Ask for delivered price per ton and legal load size, then divide.
• Spreading method. Stone spread by box blade lands differently than stone dumped and raked, and waste differs accordingly.

• Confirm the product name and tons-per-yard with the quarry, not from memory.
• Round up to the next whole ton — short loads usually cost more per ton than a modest overage.
• Ask whether the truck can reach the far end of the lane and turn around. Dumping everything at one end means you move it twice.
• Have the drainage work — ditches, culvert ends, low spots — done before stone arrives.
• Place in layers where depth exceeds a few inches, compacting between lifts.
• Re-establish crown as you spread rather than after the surface has set up.
• Keep a small reserve pile for the first few washouts instead of ordering a second delivery.

• Dividing by 12 but forgetting to divide by 27, which overstates volume by a factor of 27.
• Using a generic tons-per-yard instead of the delivered material's figure.
• Entering the total finished depth you want rather than the depth of the new lift being added.
• Skipping the compaction allowance entirely and coming up short at the end of the lane.
• Adding stone over a drainage problem season after season.
• Leaving no crown, so water runs down the wheel tracks and cuts them deeper.