Read the unit before using a coverage figure
This chart compares geometric coverage at different depths. A cubic yard is a volume; a US short ton is 2,000 pounds of weight. Their coverage figures can be compared only after stating a loose bulk density. Metric tonnes and long tons are different units and should not be substituted into the short-ton column.
Three coverage formulas
Sq ft per cubic yard = 324 ÷ depth in inchesSq ft per US short ton = 324 ÷ depth ÷ short tons per yd³Sq ft per bag = bag volume in cu ft × 12 ÷ depth| Depth | Sq ft per yd³ | Sq ft per short ton | Sq ft per bag |
|---|---|---|---|
| 1 in | 324 | 240 | 6 |
| 1.5 in | 216 | 160 | 4 |
| 2 in | 162 | 120 | 3 |
| 2.5 in | 129.6 | 96 | 2.4 |
| 3 in | 108 | 80 | 2 |
| 4 in | 81 | 60 | 1.5 |
| 6 in | 54 | 40 | 1 |
Density changes weight coverage, not yard coverage
At 3 inches one yard geometrically covers 108 sq ft regardless of the selected weight. At 1.35 short tons per yard, one short ton corresponds to 80 sq ft. At a lighter example 0.75 short tons per yard it corresponds to 144 sq ft. These are conversion examples, not certified weights for every stone sold under a material name. Ask for the quoted product’s loose weight or labeled bag yield.
Keep rounding and extra separate
At 2.5 inches the exact geometric yard figure is 129.6 sq ft. A display rounded to 130 is useful for a quick comparison; use unrounded calculations for an order. Divide your actual area by the applicable coverage figure, then apply a chosen extra allowance once. Do not add another allowance if the supplier’s quote already includes it.
Example: 500 sq ft at 3 inches
The net layer is 125 cu ft or 4.63 yd³. A selected 10% order increase gives 137.5 cu ft or 5.09 yd³: 275 half-cubic-foot bags, or about 6.88 short tons at the example 1.35 density. Rounding whole bags and rounding a bulk order are separate purchasing decisions.
Use the depth guide to review thickness questions, the density reference to understand loose weights, and the square-foot calculator for a known area. The cubic-yard calculator also works backward from volume. A coverage table does not determine a drainage or load-bearing design.
Questions about this calculation
How many square feet does one cubic yard cover?
Divide 324 by depth in inches: 162 square feet at 2 inches, 108 at 3 inches and 81 at 4 inches. These geometric figures exclude allowances and do not select an installation depth.
How many square feet does one ton cover?
For a US short ton, divide 324 by depth in inches and by the supplier’s short tons per cubic yard. At 3 inches and an example 1.35 short tons per yard, the result is 80 square feet. Different loose weights produce different coverage.
Does stone size change the volume formula?
No. Size can affect a practical layer thickness, voids and loose weight. The geometric formula stays the same. Confirm the selected product and depth instead of treating a size name as a density.
How do I estimate a 500-square-foot order from the chart?
At 3 inches and an example 1.35 short tons per yard, 500 ÷ 80 = 6.25 short tons before extra. A selected 10% increase gives about 6.88 short tons. Use unrounded inputs for the final order calculation.