At an example density of 1.40 US short tons per cubic yard, one short ton geometrically covers 115.714286 sq ft at 2 inches, 77.142857 sq ft at 3 inches or 57.857143 sq ft at 4 inches. The formula is 324 / (depth in inches × short tons per cu yd). Check the actual supplier density and volume state before using those figures for an order.
The formula
Coverage (sq ft) = delivered short tons / density (short tons/cu yd) × 324 / selected depth (in).
Short tons needed = area × depth / 324 × density. One cubic yard is 27 cubic feet, and one inch is 1/12 foot, giving the 324 factor. A US short ton is 2,000 lb; do not silently substitute a metric tonne.
The weight-to-volume conversion and chosen layer depth must refer to the same state. A loose-material density converts mass to loose volume, not automatically to compacted installed volume. The chart below has no compaction conversion, handling allowance or sales rounding. Depths are scenarios, not design recommendations.
Coverage per short ton: density sensitivity
These are three example density inputs, not a claimed universal gravel-density range. Every cell uses full-precision division and is displayed to three decimals.
| Selected depth | At 1.30 short t/cu yd | At 1.40 short t/cu yd | At 1.50 short t/cu yd |
|---|---|---|---|
| 1 in | 249.231 sq ft | 231.429 sq ft | 216.000 sq ft |
| 2 in | 124.615 sq ft | 115.714 sq ft | 108.000 sq ft |
| 3 in | 83.077 sq ft | 77.143 sq ft | 72.000 sq ft |
| 4 in | 62.308 sq ft | 57.857 sq ft | 54.000 sq ft |
| 6 in | 41.538 sq ft | 38.571 sq ft | 36.000 sq ft |
| 8 in | 31.154 sq ft | 28.929 sq ft | 27.000 sq ft |
Source density assumptions are not guarantees
OnSiteCalculator’s coverage table labels its figures loose, dry gravel and uses material-specific assumed densities.1 American Rock Supply also lists approximate calculator densities, including 1.40 short tons/cu yd for several gravel products and 1.50 for road base.2 These are the sources’ assumptions. Confirm the selected product’s current supplier value rather than treating the material name alone as a density measurement.
Three checked examples
1. Five short tons at 3 inches
At example 1.40 short t/cu yd: volume = 5 / 1.40 = 3.571429 cu yd. Coverage = (5 / 1.40) × 324 / 3 = 385.714286 sq ft. At a uniform 3-foot width, that is 128.571429 ft of length. These are geometric results in the matched state, before any separate loss or compaction conversion.
2. 400 sq ft at 4 inches
Net volume = 400 × 4 / 324 = 4.938272 cu yd. At example 1.40 density: 6.913580 short tons. A separately chosen 10% quantity allowance gives 7.604938 short tons. If the supplier sells only half-ton increments, that rounds up to 8 short tons. Allowance and increment are hypothetical inputs, not recommendations from the sources.
3. Compare two densities at 2 inches over 500 sq ft
Geometric volume = 500 × 2 / 324 = 3.086420 cu yd. At example 1.40 density, 4.320988 short tons; at 1.50, 4.629630 short tons. Difference: 0.308642 short tons. The coverage comparison is 115.714286 versus 108 sq ft per short ton. Choosing the wrong density changes the estimate even with the same area and depth.
Separate compaction from allowance
If the project specifies compacted depth but the supplier quotes loose material, calculate the installed geometry and obtain the material-specific loose-to-compacted conversion. Do not label an arbitrary extra percentage “compaction.” Keep that conversion separate from any handling allowance so it is not counted twice.
Moisture is another reason to verify the delivered material’s density/state. Do not infer a dry-volume quantity from gross wet weight using an unrelated dry-density number. The calculator cannot select the correct material, moisture basis or installed section for you.
Before buying by the ton
- Measure the actual area and added depth, including separate low spots or irregular regions.
- Confirm US short tons versus metric tonnes, exact material and quoted density basis.
- Match density and layer depth to the same volume state, or verify a conversion.
- Choose any separate allowance and confirm the actual sales increment before final round-up.
- Check delivery, access, minimum quantities and fees separately. Coverage does not establish a truck’s payload.
FAQ
How much does a ton cover at 4 inches?
At example 1.40 short t/cu yd, 57.857143 sq ft; at 1.50, 54 sq ft. The right answer depends on the actual material density and matched state, not just the word “gravel.”
How much does one cubic yard cover?
Geometrically, 324 / depth in inches: 162 sq ft at 2 inches or 81 at 4. The yard and layer depth must describe the same state. See the cubic-yard coverage guide.
Should I divide by a rounded coverage number?
Use the exact formula through the quantity and allowance steps. Rounded chart values are for display; using them as exact inputs can change a near-boundary order.
Is 1.40 the standard density for every gravel?
No. It is an example and a value used by the cited calculators for some products. Ask the actual supplier for a matched material/state value.
Related tools
Gravel calculator | Cubic-yard coverage guide | Cubic-yard formula guide
Sources
- OnSiteCalculator: Gravel Coverage Per Ton (calculator-site density and loose/dry coverage assumptions; not site design or measured supplier density)
- American Rock Supply: Gravel Calculator (supplier-specific approximate density inputs; not universal gravel values)