Gravel Calculator
Most calculators give you a volume. This one works back from the finished compacted depth you want, layer by layer, to the loose tonnage you actually have to order — and consolidates every area into one sheet for the quarry.
Build your project
Measure each area once, then stack the material layers on it. Everything consolidates into one order.
Appears on the printed and copied order sheet.
Driveways, patios, paths, pads — any straight-sided area.
Layers
Each layer sits on this same area. Enter the FINISHED compacted depth — the order works back to the loose volume you need delivered.
Compacts substantially. Order loose volume for the compacted depth you want.
Essentially non-compactible in the field. The upper bound below is laboratory maximum-density vibration, not what a plate compactor achieves.
Project settings
Applied on top of the loose volume, after compaction.
Legal load sizes vary by state and hauler — confirm with your supplier.
Prices optional
Most yards quote by the ton. Enter whichever you were given — a per-ton price is used first.
The thing that trips people up: compaction
You ask for a finished depth. The quarry sells you loose material by weight. Those are not the same volume, and the gap is large enough to leave a job short.
WSDOT publishes both figures for the same material. Crushed surfacing weighs about 2,850 lb per cubic yard as it sits on the truck and 3,700 lb per cubic yard once compacted on the roadway. Same stone, same weight — a fifth less volume. So a finished 4 inches of dense-graded base needs roughly 5 inches of loose material delivered.
Order the compacted volume and you will be about 20% short. The calculator above divides rather than multiplies, which is the whole reason it asks for the finished depth rather than the delivered one.
Open-graded, dense-graded, rounded
Which of the three a material belongs to matters more than what the rock is called. It governs whether the layer drains, whether it compacts, and whether it will hold up under a car.
| Type | What it does | Compaction |
|---|---|---|
| Dense-graded | Runs continuously from coarse stone down through sand to dust. Under a compactor the fines migrate into the voids and the layer locks into a load-bearing platform. | Compacts substantially. Order loose volume for the compacted depth you want. |
| Open-graded (clean) | Washed to a narrow size range with the fines removed. Porous, drains freely, and does not lock up under a compactor. | Essentially non-compactible in the field. The upper bound below is laboratory maximum-density vibration, not what a plate compactor achieves. |
| Rounded | Smooth, water-worn stone. Will not interlock, migrates under traffic, and is a poor choice for driveways. | Does not lock up. Treat as non-compacting. |
This is also why asking for "limestone" or "granite" by name is less useful than asking for a gradation. Density tracks the gradation far more closely than it tracks the rock type.
Materials, densities and sources
Every figure below is a range, with the source named. Densities marked approx. have no published figure for that specific product; their band comes from the governing test-method range instead, and they carry a stronger warning in the results.
| Material | Type | lb/ft³ | tons/yd³ | Compaction |
|---|---|---|---|---|
| #57 stone (¾" washed) Driveway base and surface, drainage, pipe bedding, under slabs. | Open-graded (clean) | 95.4–108.7 | 1.29–1.47 | 0–12% |
| #8 stone (⅜" chip) Top dressing, choke course over larger stone, paver joints, walkways. | Open-graded (clean) | 85.7–112.8 | 1.16–1.52 | 0–12% |
| Coarse drainage rock (#1–#3 size) Driveway sub-base over soft ground, French drains, heavy drainage layers. | Open-graded (clean) | 92–112 | 1.24–1.51 | 0–10% |
| Crusher run / dense-graded aggregate Driveway and parking base, under pavers and slabs, load-bearing platforms. | Dense-graded | 105.9–114.8 | 1.43–1.55 | 20–25% |
| Gravel base General base course beneath driveways, slabs and pavements. | Dense-graded | 103.7–114.8 | 1.40–1.55 | 18–25% |
| Ballast (coarse dense-graded) Heavy-duty base under roads and commercial paving. | Dense-graded | 110–120 | 1.49–1.62 | 18–24% |
| Screened gravel surfacing Finished driving surface on gravel roads and long drives. | Dense-graded | 103.7–116 | 1.40–1.57 | 18–24% |
| Pea gravel approx. Paths, ground cover, playgrounds, drainage. NOT a driveway surface — rounded stone will not interlock and migrates under traffic. | Rounded | 90–110 | 1.22–1.49 | 0–3% |
| River rock (1–3") approx. Decorative beds, dry creek beds, erosion control. Placed, never compacted. | Rounded | 85–105 | 1.15–1.42 | 0–0% |
| Stone dust / screenings approx. Paver and flagstone setting beds, fine grading, path surfacing. | Dense-graded | 100–120 | 1.35–1.62 | 12–22% |
| Sand approx. Paver bedding, pipe bedding, fill, general levelling. | Dense-graded | 95–118 | 1.28–1.59 | 8–18% |
Full citations for every figure are on the methodology page, which is generated from the same data this calculator reads.
Coverage: square feet per ton
| Material | 2″ deep | 3″ deep | 4″ deep | 6″ deep |
|---|---|---|---|---|
| #57 stone (¾" washed) | 120 ft² | 80 ft² | 60 ft² | 40 ft² |
| Crusher run / dense-graded aggregate | 109 ft² | 73 ft² | 55 ft² | 36 ft² |
| Pea gravel | 120 ft² | 80 ft² | 60 ft² | 40 ft² |
Calculated at each material's likely density. Coverage halves as depth doubles.
How deep?
| Use | Typical depth |
|---|---|
| Path / ground cover | 2″ |
| Drainage layer | 3″ |
| Patio or shed base | 4″ |
| Driveway (per layer) | 4″ |
| Heavy / soft ground | 6″ |
Practice-based guidance, not a standard. Soft or poorly drained ground needs more.
A layered driveway
A gravel drive is not one material. A typical build, from the subgrade up:
- Sub-base — coarse open-graded rock, 4″, to bridge soft ground and drain.
- Base — crusher run or other dense-graded material, 3–4″, compacted to carry the load.
- Surface — angular stone such as #57, 2″, for the running surface.
Each course is a different material at a different depth with a different compaction allowance, which is why they cannot be lumped into one number. Add them as separate layers above; the area is measured once and every layer derives from it.
Delivery
| Vehicle | Typical load |
|---|---|
| Tri-axle dump truck | 15–22 tons |
| Tandem / six-wheeler | 8–13 tons |
| Pickup truck | 1–2 tons |
Typical practice, not a standard — legal axle loads and body sizes vary by state and hauler. Check access before ordering a tri-axle.
Waste allowances
| Site | Allowance | When |
|---|---|---|
| Tidy site, contained area | 5% | Edged beds or a contained pad where little can spread or be lost. |
| Typical job | 10% | The usual default. Covers spillage, spreading loss and an uneven subgrade. |
| Rough or soft ground | 15% | Soft subgrade that swallows the first layer, or material handled twice. |
WSDOT advises adding 10% for waste where material is stockpiled, which is where the default comes from. The other two are practice-based judgement.
Ordering without getting caught out
- Ask for tons per cubic yard for the exact material. It is the one number that turns every figure here from an estimate into a quantity.
- Give the yard a finished depth, not a volume. They know their own material's compaction better than any table does.
- Order the whole job at once where you can. Consolidating areas into one delivery usually beats three separate loads on price.
- Check access first. A tri-axle needs room to get in, tip and turn. If it cannot, your load size — and your price per ton — changes.
- Wet material weighs more. You pay by weight, so a rained-on stockpile costs more for the same volume of stone.
Frequently asked questions
How much gravel do I need?
Multiply the area in square feet by the depth in feet to get cubic feet, divide by 27 for cubic yards, then multiply by the material’s density to get tons. The step almost every calculator skips is compaction: if you want a finished compacted depth, you have to order MORE loose material than that, because dense-graded stone densifies under a compactor. The calculator above works backwards from the finished depth you want.
Why is the tonnage shown as a range?
Because aggregate density genuinely is one. Bulk density is measured on a sample under AASHTO T 19 / ASTM C29 and depends on the source rock, the gradation and how wet it is. A Wisconsin DOT study measured 29 of that state’s own aggregates and found conversion factors spanning 1.50 to 1.98 tons per cubic yard. Any calculator quoting a single confident number is inventing precision the material does not have.
What is the difference between open-graded and dense-graded stone?
Open-graded stone such as #57 is washed to a narrow size range with the fines removed. It drains freely and is essentially non-compactible — it will not lock up under a plate compactor. Dense-graded material such as crusher run runs continuously from coarse stone down through sand to dust; under a compactor the fines migrate into the voids and the layer locks into a load-bearing platform. That difference is why the two need very different allowances.
How many inches of gravel does a driveway need?
A common build is 4 inches of coarse sub-base, 3 to 4 inches of crusher run as the base, and 2 inches of surface stone. Soft ground needs more; a firm, well-drained subgrade needs less. Add each course as its own layer above and the calculator handles the different densities and compaction for each.
Should I order gravel by the ton or by the yard?
Most quarries sell by the ton, while plans and takeoffs are usually written in cubic yards — which is exactly where ordering mistakes come from. The order sheet above shows both for every material so you can speak the yard’s language without doing the conversion in your head.
How much does a cubic yard of gravel weigh?
Broadly 1.2 to 1.6 tons, depending on the material and its condition. #57 stone measured between 95.4 and 108.7 lb/ft³ in FHWA testing, which is about 1.29 to 1.47 tons per cubic yard. Dense-graded base material is heavier once compacted — WSDOT publishes crushed surfacing at 1.85 tons per cubic yard compacted, against roughly 1.43 to 1.48 loose on the truck.
Do I need to add extra for compaction?
For dense-graded material, yes, and it is significant. WSDOT’s own figures show crushed surfacing weighing about 1.43 tons per cubic yard on the truck and 1.85 once compacted on the roadway — roughly a 22% reduction in volume. Order the compacted volume and you will be about a fifth short. Open-graded and rounded stone barely change, so their allowance is near zero.
Can pea gravel be used for a driveway?
It is a poor choice. Pea gravel is rounded, so the stones will not interlock; they migrate under tyres, rut easily and spread off the edges. It is well suited to paths, ground cover, playgrounds and drainage. For a driveway surface you want angular crushed stone, over a dense-graded base.
How many tons fit on a truck?
Typically 15 to 22 tons on a tri-axle, 8 to 13 on a tandem, and 1 to 2 in a pickup. Legal axle loads and body sizes vary by state and by hauler, so treat these as a starting point and confirm with your supplier — especially if access limits you to a smaller truck.
How much area does a ton of gravel cover?
About 120 square feet at 2 inches deep for #57 stone, 60 at 4 inches, and 40 at 6 inches. That scales inversely with depth: double the depth and you halve the coverage. The table below gives figures for several materials, using each one’s likely density.
Can I calculate several areas at once?
Yes — that is what the area list is for. Add a driveway, a path and a fire-pit surround, give each its own layers, and everything with the same material consolidates into a single order line. Ordering one combined delivery is usually cheaper than three.
Sources
Densities and compaction come from state DOT specifications, FHWA research and university publications — principally the WSDOT Design Manual for base and surfacing unit weights, FHWA-HRT-15-034 for open-graded aggregates, and AASHTO T 19 / ASTM C29 — Bulk Density ("Unit Weight") and Voids in Aggregate as the governing test method. Other calculator websites were used for feature comparison and to cross-check our arithmetic, and are never cited as a source. Every constant, with its citation and its uncertainty, is listed on the methodology page.
Last reviewed September 16, 2026.
Related
- Concrete Calculator — slabs, footings, post holes and more, consolidated into one pour.
- Cubic Yard Calculator — plain volume for any material, when you only need the yards.