Asphalt Calculator
Asphalt gets ordered by the ton, but you measure your driveway in feet and inches, so there's a conversion in the middle that trips people up. Enter your area and the depth you're paving below. The calculator works out the tonnage using standard hot-mix density, adds a little for compaction, and gives you a cost estimate so you can price the load.
How much asphalt you need, by the ton
Asphalt sells by the ton, but you measure a driveway in feet, and the two don't line up in your head. This tool bridges them: enter length, width, and thickness and you get the tonnage, the cubic yards, and a cost you can price to a local quote. It also handles the part most calculators skip, the asphalt you lose to compaction when the roller goes over it.
The math
Volume first, then weight. Length times width times thickness in feet gives cubic feet. Hot-mix asphalt runs about 145 pounds per cubic foot, so multiply cubic feet by 145 and divide by 2,000 to get US tons. That density holds for typical dense-graded hot mix; cold patch and recycled mixes run lighter, around 105 to 135 pounds per cubic foot.
Order loose, place compacted
Here's the catch the cheap calculators miss. Asphalt goes down loose and gets rolled, and it loses volume when it compacts, usually 8 to 12 percent. If your thickness is the finished, compacted depth, you have to order extra to hit it. Add a 5 to 6 percent waste margin plus the compaction allowance, and the tool builds both into the tonnage so the truck brings enough.
How far a ton of asphalt goes
A ton of hot mix is about 13.8 cubic feet placed, so coverage drops fast as the lift gets thicker.
| Thickness | One ton covers |
|---|---|
| 1 inch | ~165 sq ft |
| 2 inches | ~80 sq ft |
| 3 inches | ~55 sq ft |
| 4 inches | ~40 sq ft |
How thick to lay it, and the base under it
A residential driveway wants about 3 inches of compacted asphalt over a solid base, 4 inches in cold climates that heave. Heavy or truck traffic runs more. The base matters as much as the surface: figure 4 inches of compacted crushed stone over good soil, 8 inches over clay. Size that gravel base with the gravel calculator and order it with the asphalt so the whole section gets built once.
A real driveway example
A 12 by 40 foot driveway at 3 inches: 480 square feet times 0.25 feet is 120 cubic feet. Times 145 and divided by 2,000 is about 8.7 tons. Add the waste and compaction allowance and you order roughly 9.5 tons. Asphalt comes by the full ton and often has a minimum load, so round up to what the plant will deliver.
Ton vs tonne, and ordering
US plants quote the short ton, 2,000 pounds. A metric tonne is 2,205, so if a spec or an online figure uses tonnes, it's about 10 percent heavier. Either way asphalt is sold and delivered by the load, with a minimum and a delivery charge, so plan to order in whole tons rather than chasing an exact decimal.
Asphalt driveway cost per square foot
Installed asphalt runs $7 to $13 per square foot in most markets: roughly $2 to $3 of that is the hot mix itself, and the rest is base prep, equipment, and crew. A 24 by 40 driveway lands between $6,700 and $12,500 installed. Hot mix bought by the ton for a crew you've hired separately runs $100 to $200 a ton picked up at the plant. Compare surfaces side by side in the driveway cost calculator.
Quick answers
How thick should asphalt be? Two to 3 inches compacted for a car driveway over a solid 6-to-8-inch stone base. The base does the structural work; thin base under thick asphalt still fails.
How many tons of asphalt in a square foot? At 3 inches thick, a square foot takes about 36 pounds, so a ton covers roughly 55 square feet. The calculator runs the exact figure at any depth.
Can asphalt go over an old driveway? An overlay over sound, well-drained asphalt works and costs $3 to $7 per square foot. Over cracked or heaved pavement it just photocopies the old failures upward within a couple of winters.
When should asphalt be sealed? First seal after 6 to 12 months of curing, then every 3 to 5 years. More often looks nice and wastes money.
Common questions
Measure length and width, pick a depth (2 to 3 inches is typical for a residential driveway surface), and the calculator returns tonnage. A rough figure: a standard two-car driveway runs 15 to 20 tons.
At 2 inches deep, very roughly 1 ton covers about 80 square feet. It changes with depth, so enter your real numbers rather than relying on a flat rule.
Two to three inches of asphalt over a solid compacted base for residential work. Heavier loads or poor soil need more. The tool sizes the order for whatever depth you set.
Asphalt compacts under the roller, so loose tonnage placed is more than the finished volume, and edges and transitions eat material. A small overage keeps the crew from running thin on the last pass.
Estimates for planning. Verify against your supplier's units and your local building codes before ordering or building. For anything structural, follow your engineer or local code.