Is gravel sold by weight or by volume?

Both, depending on the supplier and region. Builders' merchants often sell by weight (tons or tonnes), while landscaping suppliers may sell by volume (cubic yards or cubic metres). They're linked by the material's density: gravel is roughly 1.4 tons per cubic yard, so knowing one lets you convert to the other.

How much does a cubic yard of gravel weigh?

About 1.4 tons (roughly 2,800 lb) for typical gravel or crushed stone. Sand and pea gravel are similar at around 1.35 tons per cubic yard, topsoil is lighter at about 1.1 tons, and mulch is much lighter still at around 0.4 tons. Moisture content pushes these figures up, since wet material is heavier.

How deep should I lay gravel?

It depends on use. A decorative gravel surface needs about 2–3 inches; a path or patio base around 3–4 inches; and a driveway that carries vehicles typically 4–6 inches of compacted gravel, often over a sub-base. Deeper layers need proportionally more material, which is why depth is a key input in any estimate.

Why does moisture change how much I should order?

Wet sand and gravel weigh more per unit volume than dry, so if you're buying by weight, damp material gives you less actual coverage than the tonnage suggests. Material also compacts when laid and settles over time, so ordering a little extra — around 5–10% — avoids coming up short.

How many tons of gravel do I need for my area?

Multiply length × width × depth to get the volume, convert to cubic yards (divide cubic feet by 27), then multiply by the material's density in tons per cubic yard. For example, a 20 × 10 ft area at 3 inches deep is about 1.85 cubic yards, or roughly 2.6 tons of gravel.

Buying Gravel, Sand and Topsoil: Why Bulk Materials Are Sold by Weight and Volume

The short version

Bulk materials are sold by weight or volume — linked by density (gravel ≈ 1.4 tons per cubic yard).
Depth drives the quantity: 2–3" decorative, 3–4" path, 4–6" driveway.
Density varies by material — mulch is light, gravel and sand are heavy.
Order 5–10% extra for compaction and settling, more if the material is wet.
To estimate volume and tonnage, use the Gravel Calculator.

"A ton" and "a yard" are not the same pile

Ordering bulk landscaping material is the one DIY task where the units genuinely trip people up, because the same stuff is sold two completely different ways. One supplier quotes tons; another quotes cubic yards. Order the wrong amount and you either run short halfway across the drive or end up with a small mountain of surplus gravel you now have to deal with. The good news: a single idea — density — connects the two, and once you've got it, estimating is quick.

Weight versus volume, and the bridge between them

Volume (cubic yards or cubic metres) measures the space the material fills. Weight (tons or tonnes) measures how heavy it is. Which one a supplier uses tends to depend on the trade — builders' merchants lean toward weight, landscaping yards toward volume — but you'll meet both.

The bridge is density: how much a given volume of the material weighs. For typical gravel that's about 1.4 tons per cubic yard. So if you've worked out you need 2 cubic yards, that's roughly 2.8 tons — and you can order confidently in whichever unit the supplier uses. The Gravel Calculator does this conversion for you, for several common materials.

Density changes everything

Not all bulk materials weigh the same, and the differences are large. Rough densities per cubic yard:

Gravel / crushed stone — about 1.4 tons
Sand — about 1.35 tons
Pea gravel — about 1.35 tons
Topsoil — about 1.1 tons
Mulch — about 0.4 tons

Mulch is less than a third the weight of gravel for the same volume. This is why you can't use one blanket "tons per yard" figure for everything — the material matters. Picking the right density is the difference between a sensible order and a wildly wrong one, so any good estimate starts by choosing the material.

Depth: the input people forget

Area is only half the picture. A patio-sized rectangle covered 2 inches deep needs a fraction of the material it would at 6 inches. Depth is set by the job:

Decorative gravel surface — 2–3 inches.
Path or patio base — 3–4 inches.
Driveway (vehicle traffic) — 4–6 inches of compacted gravel, usually over a coarser sub-base.

Going deeper than needed wastes money; going shallower risks a surface that shifts, ruts, or shows the ground beneath. Decide the depth first, then calculate — the Gravel Calculator takes area and depth together and returns both volume and tonnage.

Why you should order a bit extra

Two real-world effects mean the neat calculated figure is a minimum, not a target:

Compaction. Loose gravel settles and compacts when laid and driven on, so the finished depth is less than the loose depth. You need more loose material than the final volume suggests.
Settling and spread. Material disappears into an uneven base, spreads past tidy edges, and generally doesn't behave like a perfect box.

A 5–10% extra allowance covers this. And remember moisture: wet sand or gravel weighs more per cubic yard than dry, so if you're buying by weight, damp material gives you less coverage than the tonnage implies — another reason to round up rather than down.

A worked example

Say you're gravelling a 20 ft × 10 ft area to a 3-inch depth.

Volume = 20 × 10 × (3 ÷ 12) = 50 cubic feet
In cubic yards = 50 ÷ 27 ≈ 1.85 cubic yards
As weight = 1.85 × 1.4 ≈ 2.6 tons

Add 10% for compaction and you'd order around 2 cubic yards / just under 3 tons. Whether the supplier talks volume or weight, you're now covered either way.

Estimating your job

Pick your material, enter the area and depth, and the Gravel Calculator returns cubic yards, cubic metres, and tons. If the gravel is a sub-base under a slab, pair it with the Concrete Calculator for the pour on top.

Sources

The Mineral Products Association — aggregate density and usage guidance.
US Federal Highway Administration — typical aggregate densities and base-course depths.
Supplier technical data — tons-per-cubic-yard figures for landscaping materials.

This article is for general informational purposes. Densities are typical dry values; confirm with your supplier for the specific material.

Written by

Tufail Ahmed

Computer Scientist

Tufail builds CalcPool's calculators and writes the research behind them, turning documented formulas and primary sources into tools and explainers you can actually use.

Reviewed by Khizar Nadim · Technical Reviewer

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