Asphalt calculator
How many tons of hot mix asphalt a driveway or path needs, from its size and compacted thickness.
145 lb per cubic foot is a standard estimating figure for hot mix asphalt. If your supplier gives one for their mix, use theirs.
How to use it
Enter the length and width of the area in feet and the finished, compacted thickness in inches. Asphalt is sold by the ton, so the calculator converts the volume to weight using a density: 145 lb per cubic foot unless you change it.
How it's calculated
- Cubic feet = length × width × (thickness ÷ 12).
- Pounds = cubic feet × density.
- Tons = pounds ÷ 2,000.
At 145 lb per cubic foot, a cubic yard of compacted asphalt weighs about 1.96 tons.
| Area | 2 in thick | 3 in thick |
|---|---|---|
| 10 × 20 ft (200 sq ft) | 2.42 tons | 3.63 tons |
| 12 × 40 ft (480 sq ft) | 5.8 tons | 8.7 tons |
| 20 × 50 ft (1,000 sq ft) | 12.08 tons | 18.13 tons |
Where the density comes from
Highway departments publish densities for estimating; the Iowa DOT design manual uses 145 lb per cubic foot for hot mix asphalt. Real mixes vary with their stone and how well they're compacted, so a supplier's figure for their own mix is always better.
Tips
- Thickness is after compaction. Asphalt is laid thicker and rolled down, so order by the finished thickness and let the supplier or paver allow for compaction.
- The base matters as much as the asphalt. A residential driveway is commonly 2 to 3 in of asphalt over several inches of compacted gravel. Work out the base with the gravel calculator.