Asphalt Calculator
Tons of hot mix, millings or cold patch for a driveway, path or parking pad — from the area and compacted thickness — plus the stone base and what the job should cost installed.
Why a 3-inch driveway starts out nearly 4 inches thick
Hot mix comes off the paver loose and full of air. The roller squeezes it down about 20–25% — and you pay for asphalt by the ton, which is set by the compacted thickness. Drag the loose lay-down depth.
Compacted hot mix weighs about 145 lb per cubic foot. A crew that lays thin to save material leaves a driveway that cracks under the first delivery truck — which is why the thickness in a quote should always say compacted.
Asphalt tonnage formula
tons = area (sq ft) × thickness (in) ÷ 12 × 145 lb/ft³ ÷ 2,000
Plants sell hot mix by the ton, so the calculation turns your volume into weight. 145 lb per cubic foot (about 1.96 tons per cubic yard) is the usual figure for compacted dense-graded mix; your plant can give the exact density for its mix design.
Coverage per ton
| Compacted thickness | Sq ft per ton | Tons per 1,000 sq ft |
|---|---|---|
| 1.5 in | 110 | 9.1 |
| 2 in | 83 | 12.1 |
| 2.5 in | 66 | 15.1 |
| 3 in | 55 | 18.1 |
| 4 in | 41 | 24.2 |
| 5 in | 33 | 30.2 |
| 6 in | 28 | 36.3 |
Worked examples: tons and installed cost
Hot mix at 145 lb/ft³ with 5% waste; installed range uses $3–$7 per sq ft for a new driveway on a new base — a common US planning range, not a quote.
| Project | Area | Thickness | Tons | Installed |
|---|---|---|---|---|
| 20 × 20 ft | 400 sq ft | 3 in | 7.6 | $1,200–$2,800 |
| 12 × 50 ft | 600 sq ft | 3 in | 11.4 | $1,800–$4,200 |
| 24 × 40 ft | 960 sq ft | 3 in | 18.3 | $2,880–$6,720 |
| 10 × 100 ft | 1,000 sq ft | 2.5 in | 15.9 | $3,000–$7,000 |
| Large driveway / small lot | 2,000 sq ft | 3 in | 38.1 | $6,000–$14,000 |
Asphalt mix types and weights
| Mix | lb/ft³ (compacted) | Typical use |
|---|---|---|
| Hot mix (dense-graded) | 145 | Driveways, roads, parking — the default |
| Warm mix | 145 | Same as hot mix, produced at lower temperature; longer haul window |
| Porous / open-graded | 120–130 | Permeable paving over a stone reservoir |
| Cold patch | ≈140 | Potholes and small repairs; bags, no roller needed |
| Millings (RAP), rolled | 125–140 | Budget driveways and lanes; loose millings weigh roughly 100–120 |
Densities are typical published supplier figures; your plant’s mix design sheet gives the exact value.
What a good asphalt driveway needs
- A real base. 6–8 inches of compacted crushed stone does most of the structural work; asphalt is the wearing surface.
- Drainage. A 1–2% cross slope (⅛–¼ inch per foot) so water runs off rather than soaking the base.
- Hot, dry weather. Mix needs to arrive and compact hot; most plants close in winter.
- Sealcoat later, not now. Wait 6–12 months before the first sealcoat so the binder cures.
Questions people ask
How many tons of asphalt do I need?
Multiply area (sq ft) × compacted thickness (in) ÷ 12 to get cubic feet, multiply by 145 lb/ft³, then divide by 2,000. A 12×50-ft driveway at 3 inches is 150 cu ft × 145 = 21,750 lb, or about 10.9 tons. Add 5% for edges and waste.
How thick should an asphalt driveway be?
For a residential driveway, 2–3 inches of compacted hot-mix surface over 6–8 inches of compacted crushed-stone base is the common spec. Heavier use (RVs, delivery trucks) calls for 3–4 inches of asphalt, often laid as a binder course and a surface course. An overlay on sound existing asphalt is typically 1½–2 inches.
How much does an asphalt driveway cost?
Installed asphalt driveways in the US commonly run about $3–$7 per sq ft including base, depending on region, access and thickness. The asphalt itself is often priced at roughly $100–$200 per ton; small jobs carry mobilisation minimums.
How many square feet does a ton of asphalt cover?
At 2 inches compacted, one ton covers about 83 sq ft; at 3 inches, about 55 sq ft; at 4 inches, about 41 sq ft (using 145 lb/ft³).
How much does a 20×20 asphalt pad cost?
A 20×20 pad is 400 sq ft. At 3 inches compacted it takes about 7.3 tons of hot mix (about 7.6 with 5% waste). Installed at a typical $3–$7 per sq ft that is roughly $1,200–$2,800, but small jobs often hit a contractor’s minimum charge, so expect the top of that range or more.
How much is 2,000 sq ft of asphalt?
At 3 inches compacted, 2,000 sq ft needs about 36 tons (38 with waste). Installed at $3–$7 per sq ft, that is roughly $6,000–$14,000 including a new stone base; an overlay on sound existing asphalt costs less.
Is 2.5 inches of asphalt enough for a driveway?
For passenger cars on a well-compacted 6–8 inch stone base, 2–3 inches of compacted asphalt is the usual residential range, so 2.5 inches is workable. If trucks, RVs or a plough use the drive, go to 3–4 inches. Make sure the quote states compacted thickness, not loose.
How much asphalt millings do I need?
Millings are sold by the ton like hot mix but weigh less loose — roughly 100–120 lb/ft³ loose and 125–140 lb/ft³ once rolled. Choose “Asphalt millings” as the mix above and use 3–4 inches compacted for a driveway; order about 20–25% more loose volume than the finished depth.
What’s the difference between asphalt and blacktop?
In everyday use they are the same thing: hot-mix asphalt concrete, a blend of crushed stone and sand bound with bitumen. “Blacktop” sometimes refers to mixes with a higher proportion of stone used for driveways and roads.