Asphalt Calculator: How Many Tons for a Driveway

Measure the paved area in feet — for a rectangular driveway that is simply length × width. Enter the length and width, then set the depth in inches (2–3 inches is typical for a residential overlay, 3–4 inches for a new surface over a compacted stone base). Press calculate and you get the tons of hot-mix asphalt to order, along with the area and volume. Open More options to switch to metric, fine-tune the asphalt density, or add a price per ton for an instant cost estimate. If your driveway is not a clean rectangle, split it into rectangles, calculate each one, and add the tonnages together.

Asphalt is sold by weight — the short ton (2,000 lb) in the US, or the metric tonne elsewhere. To get from a driveway's dimensions to a weight, the calculator first finds the area (length × width), then the volume (area × depth), then multiplies by the density of the mix. Hot-mix asphalt weighs about 145 lb per cubic foot (roughly 2,320 kg/m³), though real mixes run 142–148 lb/ft³ depending on the aggregate. So if you are wondering how many tons of asphalt for a 40x20 driveway, the answer is really just volume × density ÷ 2,000. We also show a recommended order that adds 10% on top, because loose mix is rolled down to a denser, thinner layer than what you buy.

Tons = (Length × Width × Depth-in-feet × Density) ÷ 2,000

Depth is entered in inches, so it is divided by 12 to convert to feet. Using the standard hot-mix density of 145 lb/ft³:

- Area (ft²) = Length × Width
- Volume (ft³) = Area × (Depth ÷ 12)
- Weight (lb) = Volume × 145
- Tons = Weight ÷ 2,000 (one US short ton)

We then add 10% for compaction and waste to give a recommended order quantity.

A 40 × 20 ft driveway at 3 inches: Area = 800 ft². Volume = 800 × (3 ÷ 12) = 200 ft³. Weight = 200 × 145 = 29,000 lb. Tons = 29,000 ÷ 2,000 = 14.5 tons, or about 16 tons once you add 10% for compaction.

A small 20 × 10 ft parking pad at 2 inches: Area = 200 ft², volume ≈ 33.3 ft³, weight ≈ 4,833 lb ≈ 2.4 tons.

That is exactly what an asphalt calculator by the ton should return for common driveway sizes — no guesswork at the supplier.

- Order a little extra. The +10% figure covers compaction, spillage and the low spots you will not notice until you are paving.
- Depth matters more than you think. Going from 2 inches to 3 inches raises your tonnage by 50%, so confirm the spec before you order.
- Density varies. If your supplier quotes a specific mix density, enter it under More options for a tighter number.
- Hot mix cools fast. Have the base prepared and the crew ready before the truck arrives.
- Base course counts too. New driveways usually need 4–8 inches of compacted crushed stone under the asphalt — budget for that separately.