Asphalt is ordered from the plant by the ton, but a driveway is measured in feet and inches. This calculator bridges the two: it finds the volume of the area you are paving at its finished, compacted thickness, multiplies by the density of compacted hot mix asphalt and adds a small allowance for edges and uneven base. It can also estimate the crushed-stone base underneath and the cost at your supplier’s price per ton.
How to use the asphalt calculator
- Choose the area shape — a rectangle for most driveways — and enter its dimensions, or enter a known area.
- Enter the compacted thickness of the asphalt.
- Check the density. The default, 145 lb/ft³, is typical of compacted hot mix; your plant can give the exact figure for its mix.
- Set the extra percentage, usually 5–10%.
- Optionally enter a gravel base depth and a price per ton.
Asphalt formulas
As a check, the paving rule of thumb is about 110 lb of asphalt per square yard per inch of thickness, which matches a density of roughly 145–147 lb/ft³.
Worked example: a two-car driveway
Driveway: 40 × 12 ft = 480 ft². Thickness: 3 in = 0.25 ft.
Volume: 480 × 0.25 = 120 ft³; with 5% extra = 126 ft³ (4.67 yd³).
Weight: 126 × 145 = 18,270 lb ÷ 2,000 = 9.13 tons (8.29 metric tonnes).
A 6-inch gravel base adds 480 × 0.5 × 1.2 = 288 ft³, about 14.9 tons of crushed stone.
The spread rate works out to about 109 lb per square yard per inch, right in line with the field rule.
Typical thicknesses
| Use | Compacted asphalt | Compacted base |
|---|---|---|
| Walking path | 1½–2 in | 4 in |
| Residential driveway | 2–3 in | 4–8 in |
| Driveway with RVs or delivery trucks | 3–4 in (two lifts) | 8–12 in |
| Overlay on sound old asphalt | 1½–2 in | existing pavement |
These are common starting points. Soil, drainage, climate and loads all matter, and contractors often adjust the base more than the asphalt.
Ordering and paving tips
- Order by weight, in whole or half tons. Many plants have minimum loads and charge for short loads or hauling time.
- Hot mix needs to stay hot. It usually arrives at roughly 275–300 °F and has to be spread and rolled before it cools to about 175–185 °F, so have the crew and equipment ready before the truck arrives.
- Prepare the base. Most asphalt failures start with a soft or poorly drained base. Grade it for drainage, compact it, and fix soft spots before paving.
- Compact thoroughly. Rollers are what give asphalt its density and strength; uncompacted edges crumble quickly.
- Small repairs: bagged cold patch is the practical choice for potholes and cracks, sold in 50-lb bags.
Order the base with the road base calculator or the gravel calculator, using your supplier’s density. If you are weighing asphalt against a concrete driveway, the concrete calculator gives the cubic yards for the same area.
Frequently asked questions
How many tons of asphalt do I need per 1,000 square feet?
At a typical compacted density of 145 lb/ft³, a 2-inch layer over 1,000 ft² weighs about 12.1 tons and a 3-inch layer about 18.1 tons, before any extra for edges and low spots.
How much does a cubic yard of asphalt weigh?
Compacted hot mix asphalt weighs about 140–150 lb/ft³, so a cubic yard weighs roughly 3,800–4,050 lb — about 2 US tons. Paving crews often use the rule of thumb of 110 lb per square yard for each inch of thickness.
How thick should an asphalt driveway be?
Residential driveways are commonly paved with 2–3 inches of compacted asphalt over 4–8 inches of compacted crushed-stone base. Driveways that carry heavy trucks or sit on weak soil need a thicker base and are often paved in two layers.
How much area does a ton of asphalt cover?
At 145 lb/ft³, one ton is about 13.8 ft³. Spread 2 inches thick it covers roughly 83 ft²; at 3 inches, about 55 ft².
Why does the calculator use compacted thickness?
Asphalt is laid loose and then rolled, which reduces its thickness by roughly 20–25%. Plants sell it by weight, and the weight is the same before and after rolling, so tonnage is calculated from the finished, compacted thickness and density.