Box / room
Also: rectangular prism, bed, trench, room
V = L × W × H
L = length, W = width, H = height or depth.
Example: A driveway 40 ft long, 12 ft wide and 3 in thick: 40 × 12 × 0.25 = 120 cu ft × 145 lb = 17,400 lb = 8.7 tons.
Quick answer: tons of asphalt = length × width × thickness (all in feet) × 145 ÷ 2,000. A 12 × 40 ft driveway, 3 in thick, needs 12 × 40 × 0.25 × 145 ÷ 2,000 = 8.7 tons.
How to calculate asphalt tonnage
Asphalt plants sell hot-mix asphalt by the ton, so the goal is the weight of the finished layer. You need three numbers: the area, the compacted thickness and the density.
- Find the area in square feet: length × width for a rectangle, or pick another shape in the calculator.
- Convert the thickness to feet: inches ÷ 12 (3 in = 0.25 ft).
- Get the volume: area × thickness = cubic feet.
- Get the weight: cubic feet × 145 lb (a typical compacted density) = pounds.
- Convert to tons: pounds ÷ 2,000. Add about 5% for waste and low spots.
Tons = L × W × T (ft) × density (lb/cu ft) ÷ 2,000
A 12 ft wide, 40 ft long driveway with 3 in of compacted asphalt.
12 × 40 = 480 sq ft. 480 × 0.25 = 120 cu ft. 120 × 145 = 17,400 lb.
17,400 ÷ 2,000 = 8.7 tons; with 5% extra, about 9.1 tons.
Paving crews often think in square yards. A handy check: asphalt weighs about 110 lb per square yard per inch of thickness. 480 sq ft is 53.3 sq yd, × 3 in × 110 lb = 17,600 lb, which agrees with the calculation above.
Asphalt for different shapes
Most driveways are rectangles with a few extras: a curved apron at the street, a round turnaround, or an overlay that thins out where it meets a garage floor. Here are the shapes you will use, each with an asphalt example. Add each part to the project total to get one order.
Area × depth
Also: square feet to cubic feet
V = A × d
A = area, d = depth or thickness.
Example: A 600 sq ft parking pad at 2 in: 600 × 0.167 = 100 cu ft × 145 = 14,500 lb = 7.25 tons.
Cylinder
Also: round hole, post hole, tank, planter
V = π × r² × h
r = radius (half the diameter), h = height.
Example: A round turnaround 30 ft across, 3 in thick: π × 15² × 0.25 = 176.7 cu ft × 145 = 25,620 lb = 12.81 tons.
Sloped slab
Also: ramp, uneven depth, tapered bed
V = L × W × (h₁ + h₂) ÷ 2
L = length, W = width, h₁ and h₂ = depth at each end.
Example: An overlay on a 20 × 10 ft area that tapers from 2 in to 1 in to meet the garage: 20 × 10 × (0.167 + 0.083) ÷ 2 = 25 cu ft = 1.81 tons.
How thick should asphalt be?
These are typical compacted thicknesses for planning. The right design depends on your soil, drainage, climate and traffic, so follow your paving contractor’s or engineer’s recommendation.
| Job | Typical asphalt thickness | Typical gravel base |
|---|---|---|
| Overlay on sound existing asphalt | 1½–2 in | Existing pavement |
| Residential driveway | 2–3 in | 4–8 in compacted |
| Driveway for RVs or heavy trucks | 3–4 in or more | 8 in or more |
| Paths and cart paths | About 2 in | 4 in compacted |
| Commercial parking lots | 3–4 in or more, often two layers | Engineered |
Tons of asphalt per area
Read your tonnage straight off this chart, using 145 lb per cu ft. For other areas, scale up: 1,000 sq ft needs ten times the 100 sq ft figure.
| Thickness | Per 100 sq ft | Per square yard | 1 ton covers |
|---|---|---|---|
| 1 in | 0.60 tons | ≈ 109 lb | ≈ 165 sq ft |
| 2 in | 1.21 tons | ≈ 218 lb | ≈ 83 sq ft |
| 3 in | 1.81 tons | ≈ 326 lb | ≈ 55 sq ft |
| 4 in | 2.42 tons | ≈ 435 lb | ≈ 41 sq ft |
| 6 in | 3.63 tons | ≈ 653 lb | ≈ 28 sq ft |
Asphalt density and weight
The density of compacted hot-mix asphalt depends on the aggregate and the mix design. Most mixes land between about 140 and 150 lb per cubic foot once rolled; 145 lb is a common estimating number and the calculator’s default. If the asphalt plant gives you a figure for your mix, choose “Custom density” and enter it.
| Density | lb per cu ft | Tons per cu yd | kg per m³ |
|---|---|---|---|
| Lighter mix | ≈ 140 | ≈ 1.89 | ≈ 2,240 |
| Typical hot mix | ≈ 145 | ≈ 1.96 | ≈ 2,320 |
| Dense mix | ≈ 150 | ≈ 2.03 | ≈ 2,400 |
Why no compaction allowance? Crews lay hot asphalt about 20–25% thicker than the finished depth and roll it down. Rolling makes the layer thinner and denser but doesn’t change its weight. Since you enter the finished thickness and a compacted density, the tonnage is already right.
Don’t forget the base
Asphalt is only as good as what is under it. A typical driveway has 4–8 in of compacted crushed stone beneath the asphalt. You can work out the base with this calculator too: choose “Custom density”, enter about 100–105 lb for crushed stone, and set the thickness to your base depth. Or use the cubic yards calculator and pick gravel.
Asphalt cost
Asphalt prices move with crude oil, the season and the distance from the plant, so any figure on a website goes out of date quickly. Get current prices per ton from local asphalt plants or paving contractors and enter them in the calculator. Remember that a contractor’s installed price also covers excavation, base, equipment, labor and trucking, so it is quoted per square foot or square yard and is much higher than the price of the material alone.
Worked examples
Driveway with a turnaround
A 12 × 60 ft drive (720 sq ft) plus a 30 ft round turnaround (707 sq ft), both 3 in thick: 180 + 176.7 = 356.7 cu ft × 145 = 51,720 lb = 25.9 tons; with 5% extra, about 27 tons.
Two-car parking pad
20 × 30 ft at 2 in: 600 × 0.167 = 100 cu ft = 7.25 tons.
Pothole patch
A hole 3 ft across and 3 in deep: π × 1.5² × 0.25 = 1.77 cu ft × 145 = 256 lb, about five 50 lb bags of cold patch.
Notes for paving contractors
Spread rate. Tons = sq yd × thickness (in) × 110 ÷ 2,000 is the classic field check. Adjust the 110 for your mix’s compacted unit weight.
Lifts. Thick sections go down in two lifts (binder and surface). Price each lift with its own density and add tack coat between them.
Yield loss. Allow 3–5% for truck dumping, raking and edges, more on small or irregular jobs and when matching uneven existing grades.
Trucks. Highway-legal tri-axle dump trucks commonly haul somewhere around 15–20 tons depending on state weight limits. Plan deliveries so the paver doesn’t wait.
Tips
- Measure the finished edges, not the dirt; asphalt edges are tapered and slightly wider than the base.
- Plan drainage with a slight crown or slope of about 2% so water runs off.
- Seal coat new asphalt only after it has cured, often 6 months or more.
- Send the quote list to contractors with WhatsApp or Email under the result.
Frequently asked questions
How many tons of asphalt do I need?
Multiply length × width × thickness in feet to get cubic feet, multiply by about 145 lb per cubic foot and divide by 2,000. A 12 × 40 ft driveway at 3 in is 120 cu ft, which is 17,400 lb or 8.7 tons.
How much does asphalt weigh?
Compacted hot-mix asphalt typically weighs about 140 to 150 lb per cubic foot. 145 lb is a common estimating figure, which is about 1.96 tons per cubic yard.
How much asphalt per square yard per inch?
A widely used rule of thumb is about 110 lb per square yard per inch of thickness. At 145 lb per cu ft the exact figure is 108.75 lb.
How thick should an asphalt driveway be?
Residential driveways are usually 2 to 3 in of compacted asphalt over a well-compacted gravel base, often 4 to 8 in deep. Driveways that carry heavy trucks or RVs need more. Your paving contractor will set the design for your soil and traffic.
How many square feet does a ton of asphalt cover?
At 145 lb per cubic foot, one ton is about 13.8 cu ft. That covers roughly 165 sq ft at 1 in, 80 sq ft at 2 in and 55 sq ft at 3 in.
Do I need to add extra for compaction?
Not if you enter the finished, compacted thickness and use a compacted density, as this calculator does. Crews lay asphalt thicker than the final depth and roll it down, but the weight stays the same. Add about 5% for waste and uneven base.
How much does a ton of asphalt cost?
Hot-mix prices change with oil prices, region and season, and contractors price installed work by the square foot or square yard. Get current quotes from local plants or pavers and enter the price per ton to see your total.
How many tons of asphalt to fill a pothole?
Even a big pothole needs far less than a ton. A hole 3 ft across and 3 in deep is about 1.8 cu ft, roughly 260 lb. Small repairs are usually done with bagged cold patch.