How this gravel driveway calculator works
A gravel driveway is three different stones doing three different jobs, and each lift has its own density and price — so the calculator figures them as separate line items on one order:
total = top + base (+ sub-base on soft ground) · each with waste, ¼-ton steps
Set any lift to zero and it drops off the ticket — that’s how you price a bare top-up or a base-only farm lane. At the defaults — 50 × 12 ft, 3 in of #57 over 4 in of crusher run — the order is 20.5 tons and about $800; the lift-by-lift math is in the worked example below.
What are the layers of a gravel driveway?
From the dirt up: a shaped subgrade, fabric where the ground is soft, big stone where it’s truly bad, a dense base that becomes the pavement, and a clean wear course you actually drive on. Layer by layer:
Subgrade and crown
Strip the topsoil, compact what’s left, and shape a 2–3% crown — the center an inch or two proud of the edges per 10 ft of width — so water sheds sideways. Drainage is the whole secret of gravel roads; the crown is where it starts.
Geotextile fabric
On clay, silt or seasonal-wet ground, a woven geotextile between subgrade and stone stops the base from pumping into the mud. It’s the difference between a driveway and a slow-motion stone burial on soft sites.
#3 sub-base (soft ground only)
Fist-size crushed stone, 4–6 in of it, bridging ground too soft for base alone. Firm, well-drained sites skip it — leave the field at 0 and the calculator drops the lift.
Crusher-run base
The structural mat: 4 in of dense-grade with fines that locks nearly solid under a roller. This lift is the driveway — the road base calculator runs it standalone for lanes, pads and parking areas.
#57 top course
2–3 in of clean ¾ in crushed stone as the wear surface: it drains, it stays put better than anything rounded, and it’s what your tires actually touch. Decorative upgrades ride on the same base — the gravel size chart decodes the screen numbers when the quarry board gets cryptic.
Gravel driveway material options and prices
The three-lift build is the standard, but the market sells a few substitutions worth knowing — mostly trading looks or money against maintenance:
- Crusher run everywhere: some regions top with dense-grade instead of #57 — cheaper, dustier in August, harder after rain. Fine for farm lanes.
- Recycled crushed concrete: replaces crusher run at roughly half the price; the crushed concrete calculator prices the budget version of the same base.
- Asphalt millings: a self-binding top that firms up in summer heat — the halfway house between gravel and blacktop.
- Pea gravel top: pretty, migrates constantly, needs edging — a courtyard finish, not a working lane.
- Full blacktop: same base, paved top — the asphalt calculator prices that version by the ton.
| Stone | Typical range |
|---|---|
| #57 clean (top) | $35–60 |
| Crusher run (base) | $30–50 |
| #3 stone (sub-base) | $25–45 |
| Crushed concrete | $20–40 |
| Asphalt millings | $10–30 |
How much gravel for a driveway by size?
Table 2 prices whole driveways through the engine at the default build; Table 3 is the lift spec. Rule of thumb from the same math: about 3.4 tons per 100 ft² at 3 over 4.
| Driveway | Stone | Cost |
|---|---|---|
| 40 × 10 ft | 13.75 t | $536 |
| 50 × 12 ft | 20.5 t | $800 |
| 100 × 12 ft | 41 t | $1,600 |
| 200 × 12 ft | 82 t | $3,200 |
| Lift | Depth | t/yd³ |
|---|---|---|
| #57 top course | 2–3″ | 1.35 |
| Crusher-run base | 4″ | 1.5 |
| #3 sub-base (soft) | 4–6″ | 1.4 |
How to measure a driveway for gravel
Drives are long and skinny, so length errors cost more than width errors — walk it with a wheel or pace it twice. Dimension fields take feet-inches (50, 50 ft 6 in) or metric (15 m).
- Measure the length along the centerline — curves included, the way a measuring wheel rolls it, not the straight-line shortcut.
- Set the width: 10–12 ft single lane, 20–24 ft double. Add flares, pads and turnarounds as separate rectangles and sum them with the square footage calculator.
- Pick lifts by ground: firm and drained → 3 in top over 4 in base; clay or seasonal mud → add the 4–6 in #3 sub-base and the fabric.
- Refreshing an existing drive? Zero out base and sub-base and price the 1–2 in top-up alone.
- Leave waste at 10% for compaction and edge spill — the roller eats volume just like the plate compactor does.
- Enter each lift’s per-ton quote. Same-quarry lifts share the truck: a tandem hauls about 15 tons, so the default job is two loads any way you split it.
Worked example: stone for a 50 × 12 ft gravel driveway
The defaults, worked lift by lift — 600 ft², 3 in of #57 over 4 in of crusher run, firm ground, 10% allowance, $45/$35 per ton:
top = 600 × (3 ÷ 12) = 150 ft³ = 5.56 yd³ × 1.35 = 7.5 t × 1.10 → 8.25 t ≈ $371
base = 600 × (4 ÷ 12) = 200 ft³ = 7.41 yd³ × 1.5 = 11.11 t × 1.10 → 12.25 t ≈ $429
total = 8.25 + 12.25 = 20.5 tons ≈ $800
soft ground? + 4″ of #3 = 11.5 t more → $1,145 total
Notice the base outweighs the top half again despite being only an inch deeper — crusher run’s 1.5 t/yd³ compacted density is doing that. Per square foot the stone package lands at $800 ÷ 600 ≈ $1.33/ft², which is why gravel stays the cheapest driveway on the menu.
What this gravel driveway estimate doesn’t include
The calculator prices the stone. The dirt work around it is where long driveways earn their machine bills:
- Stripping and excavation. Topsoil off, grade cut, spoil hauled — machine hours, not tonnage.
- Grading and crown. Box blade or grader time to shape the 2–3% crown, plus ditching where the lane cuts a slope.
- Culverts. Any drive crossing a ditch or swale needs pipe sized and set — often a permit item at the road.
- Geotextile fabric. Commonly $0.15–0.50 per ft² on soft ground, under the first stone.
- Compaction equipment. Plate compactor for pads, a roller for real lengths — rental by the day.
- Edging and aprons. Timber or steel edges where the lawn meets the lane, and the municipality’s rules at the road end.
- The maintenance cycle. A 1 in top-up every few years and an annual regrade — cheap, but honest owners budget it.
Gravel driveway FAQ
How much does a gravel driveway cost?
The default 50 × 12 ft drive prices at about $800 in stone — 8.25 tons of #57 top course plus 12.25 tons of crusher-run base. Installed with grading and compaction, gravel driveways typically run $1.25–3 per square foot in 2026, still the cheapest driveway there is.
How much gravel do I need for my driveway?
Figure each lift separately, which is what this calculator does: at 3 in of top over 4 in of base, plan roughly 3.4 tons per 100 ft² of driveway. The default 600 ft² drive totals 20.5 tons across the two lifts with a 10% allowance.
What are the layers of a gravel driveway?
Bottom to top: 4–6 in of #3 stone only where the ground is soft, 4 in of crusher run that compacts into the structural mat, and 2–3 in of clean #57 as the wear surface. Each lift gets compacted before the next goes down.
How thick should a gravel driveway be?
7 inches compacted total on firm ground — the default 3 over 4 — and 11 or more over clay or wet ground once the sub-base joins. A thin single lift is the classic mistake: it ruts the first wet week.
How wide should a gravel driveway be?
10–12 feet for a single lane — the calculator’s 12 ft default gives car doors room — and 20–24 feet where two cars pass or park side by side. Add a flare at the road and a turnaround pad if the run is long; every widening is the same per-square-foot stone math.
How often does a gravel driveway need new gravel?
Plan a 1 in top-up of #57 every 2–4 years as traffic scatters the wear course: about 2.75 tons (≈ $124) on the default 600 ft² drive. Regrade the crown when you top up — the stone lasts far longer when water sheds sideways instead of running down the ruts.
Can I skip the base and just add gravel?
Only when refreshing an existing driveway that already has a sound base — set the base lift to 0 and price the 2 in top-up alone. On new ground, #57 without a compacted base migrates and sinks; the base is the driveway.
Gravel or asphalt driveway?
Gravel wins on price (a fraction of asphalt), repairs (rake and top up), and DIY reach. Asphalt wins on plowing, dust and curb appeal. Same site, both need the identical compacted base — price the blacktop version with the asphalt calculator.
Sources and standards
The lift build and maintenance practice here follow the people who keep unpaved roads alive for a living:
- Gravel-road maintenance guides published by state and county road agencies — the source of the crown, lift and drainage practice on this page.
- AASHTO M43: the #3 and #57 size designations the lifts are ordered by.
- Regional dense-grade specs (CA-6, Class 5, 21A, ABC): what “crusher run” means at your quarry.
- The scale ticket: lift densities are estimating figures — the weighed load governs, and this page gets the order right.
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