Asphalt Calculator
Order 20 tons of asphalt.
| Figure | Value |
|---|---|
| Area | 1,000 ft² (111 yd²) |
| Compacted volume | 9.26 yd³ |
| Exact tonnage | 18.13 tons |
| With 5% waste | 19.03 tons |
| Order (whole tons) | 20 tons |
| Trade check lb per yd² per inch | 109 lb |
Calculated at 145 lb per cubic foot of compacted hot mix — the standard estimating figure, with real mixes running 140–150 depending on aggregate and how well it is rolled. That works out to about 109 lb per square yard per inch of depth, which is the cross-check paving crews use in their heads. Thickness here is the compacted depth, not the loose depth you spread: hot mix compacts by roughly 25%, so 3 in finished needs about 4 in laid. Not included: the aggregate base beneath the asphalt (usually 4–8 in of crusher run, which often costs more than the asphalt), tack coat, excavation, grading, or edge restraint. Asphalt must be laid hot and rolled immediately, which is why this is rarely a DIY job.
Enter your area and compacted thickness to find how many tons of asphalt you need, with density, waste, and cost per ton.
How to use this calculator
- Enter the area as a rectangle or circle. For an irregular driveway, break it into rectangles and add the results.
- Set the compacted thickness — the finished depth, not the loose depth you spread.
- Adjust the density if your supplier quotes a different figure. 145 lb/ft³ is standard.
- Add a price per ton for a material cost. Remember this is asphalt only.
The formula
Cubic feet = Area (ft²) × (Thickness (in) ÷ 12) · Tons = Cubic feet × Density ÷ 2,000
Cross-check: 1 yd² at 1 in ≈ 110 lb · Order = Tons × Waste, rounded up to whole tons
Worked example — a 50 × 20 ft driveway
3 in compacted, 145 lb/ft³, 5% waste.
- Area: 50 × 20 = 1,000 ft²
- Volume: 1,000 × 0.25 = 250 ft³
- Weight: 250 × 145 = 36,250 lb = 18.1 tons
- With 5% waste: 18.1 × 1.05 = 19.03 tons — order 20 tons, since asphalt is sold by the whole ton
- At $120/ton: about $2,400 in asphalt
Cross-check with the trade rule: 1,000 ft² is 111 yd², at 3 inches that is 333 yd-inches, and at 110 lb each that is 36,600 lb — 18.3 tons. Close enough to confirm the arithmetic.
Compacted, not loose
This is the single most common error in asphalt estimating. Hot mix arrives loose and fluffy and is compacted by the roller to roughly 75% of the depth it was spread at. The thickness you specify, pay for, and measure afterwards is the compacted depth.
So a 3-inch driveway is spread at about 4 inches and rolled down. If you measure the loose mat, conclude you have hit 4 inches, and stop ordering, you finish about a quarter short of your specification. Conversely, if you enter a loose depth into a calculator you over-order. Always work in finished depth.
Thickness by application
| Application | Compacted asphalt | Aggregate base |
|---|---|---|
| Overlay on sound pavement | 1.5–2 in | Existing |
| Residential driveway | 2–3 in | 4–6 in |
| Commercial lot, light truck | 3–4 in | 6–8 in |
| Heavy truck, industrial | 4–6 in, often in two lifts | 8–12 in |
The base matters more than the asphalt
Asphalt is a flexible pavement. It does not span or carry load the way a concrete slab does — it spreads load over the base beneath it, and the base spreads it over the subgrade. That means the aggregate base is doing most of the structural work, and it is where nearly all driveway failures start.
A driveway that alligator-cracks, ruts under a parked car, or develops potholes at the edges almost always has a base problem: too thin, poorly compacted, or built over soft or wet subgrade. Adding more asphalt on top of a bad base buys a couple of years at most.
Four to six inches of well-compacted crusher run is the residential baseline, more where frost is deep or the soil is soft. The base frequently costs more than the asphalt above it, and that is money well spent — use the gravel calculator to size it.
What this calculator does not include
- The aggregate base, which is a separate and usually larger material order.
- Excavation and grading, including hauling away the spoil.
- Tack coat between lifts or against existing pavement.
- Edge restraint, and the extra material at thickened edges.
- Labour and equipment, which dominate the installed price. Materials are typically a third to a half of a paving quote.
- Plant minimums. Many suppliers have a 1 to 3 ton minimum load, so a small patch may cost more than its tonnage suggests.
Common mistakes to avoid
- Using loose depth instead of compacted. A quarter of the order, gone.
- Skimping on the base. The base carries the load. Thin base, short life.
- Paving over soft or wet subgrade. Fix the drainage first or the pavement will fail regardless of thickness.
- Ordering short. Asphalt cools. A partial load arriving an hour later cannot be knitted into the mat properly, leaving a cold joint that opens up.
- Forgetting the slope. Asphalt must shed water — a minimum of about 2% cross-slope. Flat driveways pond, and standing water is what breaks pavement apart.
How we calculate this
Volume is area × compacted thickness, and tonnage is volume × density. The default of 145 lb/ft³ is the standard estimating figure for compacted hot mix; real mixes run 140–150 depending on aggregate and compaction, and the field is editable so you can use your supplier's number. The cross-check shown in the results is the trade's own: one square yard at one inch is 0.75 ft³, which at 145 lb/ft³ is about 109 lb — the familiar "110 pounds per square yard per inch". Waste defaults to 5%, lower than most materials because paving is a continuous placement with little offcut. The order figure rounds up to whole tons.
Sources
Frequently asked questions
How many tons of asphalt do I need for a driveway?
A 50 by 20 foot driveway at 3 inches compacted is 1,000 square feet, which works out to 250 cubic feet of asphalt. At the standard 145 pounds per cubic foot that is 36,250 pounds, or 18.1 tons. Adding a 5% allowance gives 19.03 tons, and since asphalt is sold by the whole ton you would order 20.
How much does asphalt weigh per cubic foot?
Compacted hot mix asphalt runs about 145 pounds per cubic foot, with real mixes falling between 140 and 150 depending on the aggregate and how thoroughly it is rolled. A useful cross-check that paving crews use: one square yard at one inch thick weighs about 110 pounds.
How thick should an asphalt driveway be?
Two to three inches of compacted asphalt over a properly prepared aggregate base for a residential driveway. Go to three or four inches for a commercial lot or anywhere light trucks park, and four to six for heavy truck traffic. A resurfacing overlay on sound existing pavement can be 1.5 to 2 inches.
Does asphalt thickness mean compacted or loose?
Compacted, always — that is the finished depth you specify and pay for. Hot mix compacts by roughly 25% under the roller, so 3 inches finished needs about 4 inches spread loose. If you measure the loose depth and treat it as the finished thickness, you will end up about a quarter short.
How much base do I need under asphalt?
Four to eight inches of compacted crusher run or dense-graded aggregate for a residential driveway, and more in areas with deep frost or soft subgrade. The base is what actually carries the load — asphalt is a flexible surface that spreads it. Base failures cause the great majority of driveway failures, and the base often costs more than the asphalt on top of it.
How much does an asphalt driveway cost?
Hot mix typically runs $100 to $150 per ton delivered, so the asphalt for a 1,000 square foot driveway at 3 inches is roughly $1,900 to $2,900. Installed cost is considerably higher once base, excavation, grading, equipment, and labour are counted — usually $3 to $7 per square foot in total. This calculator prices the asphalt only.
Can I lay asphalt myself?
Realistically, no, for anything larger than a patch. Hot mix arrives at around 300°F and has to be spread and rolled before it cools below roughly 185°F, which means a paver, a roller, and a crew working fast. Cold patch products exist for potholes and small repairs, but they never reach the density or lifespan of hot mix.
How is asphalt sold — by the ton or by the yard?
By the ton, essentially always. Your measurements give you a volume, so the conversion by density is the step that matters, and it is exactly what this calculator does. Plants also usually have a minimum load, often 1 to 3 tons, so a very small job may pay for more than it uses.