🚧 Gravel Driveway Calculator

Enter your driveway or path length, width and depth to estimate cubic yards and tons of gravel needed.

Length (ft)

Width (ft)

Depth (in)

Density (lb per cubic ft)

From dimensions to yards and tons

Depth is converted from inches to feet and multiplied by the area to give cubic feet. Dividing by 27 gives cubic yards, which is how gravel is measured, and multiplying by the density gives the weight, which is how it is usually sold.

cubic feet  = length x width x (depth(in) / 12)
cubic yards = cubic feet / 27
tons        = cubic feet x density(lb/cu ft) / 2000

A 50 x 12 ft driveway at 4 in deep is 200 cubic feet, 7.41 cubic yards, and 10 tons at the default 100 lb per cubic foot.

Density, and why yards and tons disagree

Yards measure space, tons measure weight, and the number that links them is the density of the specific stone. These are loose as-delivered figures and they vary by quarry, so a supplier's own tons-per-yard for the product you are buying beats any table:

Material	lb per cu ft	Approx tons per cu yd
Pea gravel, river rock	95-105	1.3-1.4
Crushed stone, 3/4 in clean	100	1.35
Crusher run with fines	105-120	1.4-1.6

Order more than the hole measures

The result is the finished, compacted volume. Loose gravel does not stay loose: rolled or simply driven on, most aggregate settles 15 to 25%, and crusher run with fines settles the most because the fines migrate down into the voids. On top of that, some of the first load disappears into a soft subgrade and never comes back, and spreading always leaves a shortfall at the edges.

Add 20% for compaction on a driveway - 7.41 yards becomes about 8.9, or roughly 12 tons instead of 10.
Run the numbers per layer. A driveway is usually a 4 in base of larger stone with 2-3 in of smaller stone on top. Calculate each layer separately; they have different densities and different prices.
Round up to whole loads. Delivery is the expensive part, and a second half-load trip usually costs more than the extra ton.

Depth is dictated by the ground, not by preference. Four inches works over firm, well-drained subgrade; soft clay wants 8-12 in built in layers over a geotextile, or the stone simply sinks. Where a driveway meets a public road the apron is often the highway authority's business and may need a permit, and that requirement overrides whatever depth you had in mind.

Frequently asked questions

How many tons of gravel for a 50x12 ft driveway?

At 4 in deep, 7.4 cubic yards, which is about 10 tons of typical crushed stone. Order nearer 12 tons so there is enough left after compaction and after the base soaks up the first load.

How many tons is a cubic yard of gravel?

About 1.35 tons for ordinary crushed stone, since a cubic yard is 27 cubic feet at roughly 100 lb each, or 2,700 lb. Wet material and stone with fines in it run heavier, up to about 1.6 tons per yard.

How deep should a gravel driveway be?

4 in of stone over ground that is already firm and drains. Over soft or clay soil, 8-12 in placed in two or three compacted layers, largest stone at the bottom. A thin layer on soft ground turns into ruts within a season no matter how good the gravel is.