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Gravel Calculator

A 40 by 10 ft driveway at 4 inches deep needs 4.94 cubic yards, about 6.91 tons. That covers one layer. A driveway with a compacted base plus a decorative topping needs this run twice, once for each depth and stone type.

Project specs

Material needed

Tons needed0
Cubic yards0
Cubic feet0
Estimated cost0

One layer's total. Run again at a different depth if the project has a separate base and topping layer.

Most gravel projects are two layers, not one

A driveway or path is rarely a single pour of one gravel type. It's typically a compacted base layer that carries the load, topped with a thinner decorative or leveling layer that you actually see and walk on. These two layers use different stone sizes at different depths, so pricing them as one flat number under-orders the base and over-orders the topping more often than not.

LayerTypical depthStone type
Compacted base4 to 6 inchesAngular crushed stone that locks together under weight
Decorative or leveling topping1 to 2 inchesSmaller, often rounded or colored stone chosen for appearance and drainage
Formula: cubic feet = length x width x (depth in inches / 12). Cubic yards = cubic feet / 27. Tons = cubic yards x 1.4.

The 1.4 tons per cubic yard figure used here is Omni Calculator's published density for standard crushed stone. Washed or decorative stone can weigh somewhat less; dense traprock somewhat more.

A worked example with both layers

Take the 40 by 10 driveway above. A 4 inch base layer needs 4.94 cubic yards, about 6.9 tons, roughly $277 at $40 per ton. Add a 1.5 inch decorative topping over the same footprint and that's another 1.85 cubic yards, about 2.6 tons, likely priced higher per ton since decorative stone typically costs more than base material. Run each layer through the calculator separately with its own depth and price to get an honest combined total instead of averaging the two into one depth number, which would under-order the base.

Sequencing the two layers

Spread and compact the base layer first, in the lifts your supplier recommends, and let it set before the topping arrives. Ordering both layers for the same delivery day usually just means two piles competing for space on site, and topping stone left sitting next to base material tends to get contaminated with fines before you're ready to spread it. Schedule the topping delivery for after the base is compacted, not the same morning.

Measuring the footprint

For a rectangle, multiply length by width. For an L-shaped drive, split it into two rectangles and add them. Measure the base layer's depth from the sub-grade (the dug-out native soil), and measure the topping layer's depth from the top of the compacted base, not from the original ground, or the topping order will run short.

Buying notes

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FAQs

Should I run this calculator twice for a base layer and a topping layer?

Yes, if the project has both. A compacted base and a decorative or leveling topping usually use different stone sizes at different depths, so total them separately, then combine only the delivery scheduling, not the tonnage, into one order if the supplier can bring both in one trip.

How is a driveway base layer different from a decorative topping?

A base layer uses angular, crushed stone that compacts and locks together to carry vehicle weight, typically 4 to 6 inches deep. A topping layer is thinner, often 1 to 2 inches, and prioritizes appearance and drainage over load-bearing strength, so it's usually a different, smaller stone.

Does the base layer need to be compacted before I add a topping layer?

Yes. An uncompacted base will keep settling under a topping layer, creating low spots and ruts within a season. Compact the base in the lifts your supplier recommends and let it set before spreading a decorative or finishing layer on top.

How do I plan gravel delivery for a project with two layers?

Schedule the base layer delivery first and allow time to spread and compact it before the topping layer arrives. Ordering both layers in the same delivery usually just means two piles to manage on site at once, with the topping stone often getting contaminated by base material before you're ready for it.

What depth should I use if I have not decided between a base and a finished topping yet?

Estimate the base layer first, since it is the larger volume and the one that has to go down before anything else. Plan the topping layer as a separate, later calculation once you know how much cover the finished surface needs over that compacted base.