Gravel & Crushed Stone Calculator

Note: Cubic yards is the reliable number here. The tonnage depends on stone size and how wet the load is, so treat it as approximate and ask your supplier for their own density before ordering by weight. (Figures checked 2026-09.)

How to use this calculator

Measure the area. Length and width in feet. Driveways bend and paths widen — split anything that is not a plain rectangle into sections and the areas are added together.
Set the depth. Three inches for a path, four under a patio, six for a driveway base. The preset buttons say which is which.
Pick the material. Changing it sets a typical density, and you can type over that figure — if your supplier gave you their own number, use theirs.

The answer you should act on is the cubic yards. Tonnage is shown underneath because some suppliers price by weight, but it is a conversion, not a measurement.

The formula

volume (cubic feet) = area (sq ft) × depth (in) ÷ 12
cubic yards = cubic feet ÷ 27
tons = cubic yards × density (tons per cubic yard)

Worked example — a 40 ft × 10 ft driveway, 4 inches of crushed stone:

Area: 40 × 10 = 400 sq ft
Volume: 400 × (4 ÷ 12) = 133.3 cubic feet
In cubic yards: 133.3 ÷ 27 = 4.94 cubic yards
Rounded for ordering: 5 cubic yards
At 1.4 tons per yard: 4.94 × 1.4 = 6.9 tons

Five yards of crushed stone is roughly 14,000 lb. This is not a material you collect yourself in a pickup.

Coverage per cubic yard

Same geometry as any other spread material: one cubic yard covers 324 square feet one inch deep.

Depth	Coverage per cubic yard
1 in	324 sq ft
2 in	162 sq ft
3 in	108 sq ft
4 in	81 sq ft
6 in	54 sq ft

How deep, and for what

Depth	Use
2 in	Decorative beds, top-dressing existing stone
3 in	Walkways and garden paths
4 in	Compacted base under a patio, shed or slab
6 in	Driveway base, or ground that drains badly

Depth is doing less work than people expect. Gravel spread over soft, un-compacted ground will sink into it regardless of how much you put down — what stops that is compaction, and a geotextile separation fabric rated for the load. For a decorative bed or a path, ordinary landscape fabric underneath is worth it, mostly to stop the stone slowly disappearing into the soil.

For a slab or patio base, aim to compact in lifts of no more than about 4 inches at a time. A 6-inch base dumped in one go and rolled over once is not compacted; it is just deep.

Why the tonnage is the soft number

Aggregate is sold by volume or by weight depending on the supplier, and converting between the two is where the uncertainty lives.

The widely used figure for gravel and crushed stone is 1.4 tons per cubic yard, and retail bulk listings back it up — a common drainage rock sold at 900 lb per 8.91 cubic feet works out to 1.36 tons per yard. But the same product varies:

Water. A load that sat through a rainstorm can be noticeably heavier than the same stone dry.
Stone size and shape. Larger, more angular stone packs with more air space between pieces; fine crushed material with dust in it packs denser.
Screening. Washed stone and pit-run material of the same nominal size do not weigh the same.

None of that changes how many cubic yards fill your driveway. It only changes what those yards weigh. So: measure in yards, and if you must buy by the ton, ask the yard what their material runs and type it into the density field above.

Typical densities

Material	Tons per cubic yard
Crushed stone / gravel	1.4
Pea gravel	1.35
River rock	1.35
Sand	1.35
Screened topsoil	1.1
Compost	0.6

These are starting points for the arithmetic, not specifications. Your supplier’s number is the one that governs your invoice.

Delivery, not collection

A cubic yard of crushed stone is around 2,800 lb. The payload of a typical half-ton pickup is roughly 1,500 to 2,000 lb, so one yard is already more than most half-ton trucks should carry — and a load that fits in the bed by volume can still be well over what the suspension and brakes are rated for.

Gravel is the material where delivery stops being a convenience and becomes the sensible option. Have somewhere in mind for the pile to land, and remember it has to be moved by wheelbarrow from wherever the truck can reach.

This is an estimate. Cubic yards is solid arithmetic on the dimensions you entered. Tonnage inherits whatever uncertainty is in the density figure — confirm it with your supplier before ordering by weight.

Frequently asked questions

How many tons of gravel are in a cubic yard?

About 1.4 tons for crushed stone, and a little less for pea gravel and river rock. It is not a fixed number — the same material weighs more after rain and varies with stone size — so if you are buying by the ton, ask the supplier what their material actually runs.

How deep should gravel be?

Two inches for decorative beds, three for a walkway, four for a patio or slab base, and six for a driveway base or ground that drains poorly. Deeper is not always better: gravel over soft ground needs a compacted base or a geotextile fabric more than it needs another inch of stone.

How much area does a cubic yard of gravel cover?

One cubic yard covers 324 square feet one inch deep. That is 162 sq ft at 2 inches, 108 sq ft at 3 inches, and 81 sq ft at 4 inches — the same arithmetic as mulch, because it is the same geometry.

Should I order by the yard or by the ton?

By the yard when you can. Cubic yards is what you actually measured; tons is a conversion that depends on the material. If the supplier only sells by weight, use the tonnage here as a starting figure and confirm their density.

Do I need landscape fabric under gravel?

For a decorative bed or a path, yes — it keeps the stone from working down into the soil and disappearing over a few seasons. Under a driveway or a slab base you want compaction rather than fabric, or a proper geotextile rated for the load, not the thin weed barrier sold in garden centres.

Will a cubic yard of gravel fit in my pickup?

One cubic yard of crushed stone weighs roughly 2,800 lb — that is already at or over the payload of most half-ton pickups. Gravel is one of the materials where delivery is usually the right answer, even for small jobs.