Calculator 02 / Gravel & Aggregate
Gravel Calculator
Gravel is priced by weight but measured by volume, so the tonnage depends on the material's density as much as on the size of the hole. Estimate tons of gravel, crushed stone, sand, or topsoil for a driveway, base course, or fill area.
How this calculator works
Gravel and aggregate are sold by weight (tons), but you measure the job by volume. This tool converts your area and depth to cubic yards, then applies the material's density to get tons.
Worked example: a 20 × 12 ft driveway base
A 20 ft × 12 ft parking pad, 4 in of paver base at 105 lb/ft³, 10% waste:
- Area = 20 × 12 = 240 sq ft
- Depth = 4 ÷ 12 = 0.333 ft
- Volume = 240 × 0.333 = 80 cu ft
- Order volume = (80 × 1.10) ÷ 27 = 3.26 cubic yards
- Weight = 80 × 105 × 1.10 = 9,240 lb = 4.62 tons
- Weight without waste = 8,400 lb = 4.20 tons
Note that the yardage and the tonnage both carry the waste factor. They are two ways of describing the same order, and a supplier who quotes by the yard and one who quotes by the ton should be pricing the same pile.
What one cubic yard covers
A cubic yard is 27 cubic feet, so coverage is simply 324 divided by the depth in inches. This is the fastest sanity check on any quote — if the yardage does not roughly match your area at your depth, something is wrong.
| Depth | Area per cubic yard | Typical use at this depth |
|---|---|---|
| 1" | 324 sq ft | Top dressing only |
| 2" | 162 sq ft | Decorative rock, light paths |
| 3" | 108 sq ft | Walkways, landscape beds |
| 4" | 81 sq ft | Patio base, light driveway |
| 6" | 54 sq ft | Driveway base, heavier traffic |
| 12" | 27 sq ft | Trench drains, poor subgrade |
How deep to go
Depth is set by what the surface has to carry and by what is underneath it. Soft or clay subgrade needs more; compacted stable soil needs less.
| Application | Depth | Notes |
|---|---|---|
| Garden path / walkway | 2–3" | Over landscape fabric |
| Paver or slab base | 4–6" | Plus about 1" of bedding sand |
| Driveway, stable soil | 4–6" | Compact in two lifts, not one |
| Driveway, soft or clay soil | 8–12" | Consider geotextile beneath |
| French drain / trench | 12"+ | Washed stone, no fines |
Which aggregate to ask for
Suppliers work in size numbers, not descriptions. Asking for "gravel" gets you whatever is nearest the loader. The distinction that matters most is whether the product contains fines: material with fines locks together and compacts, washed material stays loose and drains.
| Ask for | Size | Compacts? | Use |
|---|---|---|---|
| Crusher run / #411 | ¾" to dust | Yes | Base under pavers, driveways |
| #57 stone | ¾" | No — washed | Drainage, driveway surface |
| #8 stone | ⅜" | No — washed | Paver bedding, fine drainage |
| #4 stone | 1–1½" | No | Heavy base, erosion control |
| Pea gravel | ⅜" rounded | No — rounds roll | Decorative only; never as base |
| Stone dust / screenings | Fines | Yes | Paver setting bed |
Density, and tons per cubic yard
The dropdown carries a density in pounds per cubic foot. Multiplied by 27 and halved by 2,000, that is the tons-per-yard figure a supplier will quote you. Moisture moves these numbers more than most people expect — a rained-on pile can weigh 10–15% more than the same volume dry, and you pay for the water.
| Material | Density | Tons per cubic yard |
|---|---|---|
| Gravel / paver base | 105 lb/ft³ | 1.42 |
| Crushed stone | 100 lb/ft³ | 1.35 |
| Sand | 100 lb/ft³ | 1.35 |
| Decorative / river rock | 95 lb/ft³ | 1.28 |
| Topsoil | 76 lb/ft³ | 1.03 |
Where aggregate orders go wrong
- Compaction is not waste. Crusher run loses roughly a fifth of its loose volume when properly compacted. If you need 4 inches after compaction, order for about 5 inches loose. The waste factor covers spillage and over-dig, not compaction — add for it separately.
- Mixing up yards and tons. They are not interchangeable and the ratio changes with the material. Quote both to your supplier and let them reconcile.
- Using rounded stone as a base. Pea gravel and river rock never lock together. Under pavers they migrate, and the surface goes wavy within a season.
- Measuring the finished grade. Depth means excavated depth. If you measure down from where the surface will end up, you are a full course short.
- Ignoring delivery minimums. Most yards will not tip less than a full ton, and many charge the same for a partial load as a full one. Round up to the truck, not to the estimate.
Where these numbers come from
The size numbers on a quarry ticket come from a published gradation standard, not a local naming habit — which is why a #57 means the same thing in two different states.
- ASTM D448 — The standard sizes of coarse aggregate, and the source of the #4, #57 and #8 designations.
- National Stone, Sand & Gravel Association — Industry body for aggregate producers; product descriptions and specification guidance.
- USGS construction sand and gravel statistics — Published data on aggregate production and typical material properties.
How deep should a gravel driveway base be?
A common base course is 4–6 inches of compacted gravel; heavier vehicle traffic or soft subgrade may call for 8+ inches, often in two compacted lifts.
Why does the same volume weigh differently depending on material?
Density varies by rock type, particle size, and moisture content. Always confirm density with your supplier's spec sheet for the exact product you're ordering.
Should I order by the ton or by the cubic yard?
Whichever your supplier quotes in — this calculator gives you both, and both include the waste factor, so they describe the same order. Yards are the safer unit to argue in, because a yard is a fixed volume while a ton of wet material occupies less space than a ton of dry. If a quote is priced by weight, ask what density they are assuming.
Does the waste factor cover compaction?
No, and this catches people out. Waste covers spillage, over-dig and the material left in the truck. Compaction is separate: crusher run and other products with fines lose roughly 20–25% of their loose volume once rolled. If your target is a compacted depth, either add that on top of the waste factor or enter a loose depth about a quarter deeper than the finished one.
Why is the order volume larger than the plain volume?
Because it includes your waste factor, matching the tonnage above it. The plain volume line is the raw geometry of the excavation. The order volume is what to actually buy. An earlier version of this calculator omitted the waste factor from the yardage while including it in the tonnage, so the two disagreed — that is fixed.
Can I save, share, or print a calculation?
Yes — use the Save, Copy link, and Print buttons under your results. Saved calculations can be grouped into a named project on the My Projects page for a combined job estimate with cost totals. Everything is stored only in your browser, never uploaded — see the Privacy Policy for details.
Estimates only. Suppliers typically sell in fixed ton increments — confirm exact yardage and delivery minimums before ordering.