How to use the asphalt calculator
- Measure the length and width of the area in feet. For a curved driveway, split it into rectangles and add the square feet.
- Enter the compacted thickness. Asphalt is laid loose and rolled down, and suppliers quote tonnage for the finished, compacted depth.
- Enter the depth of the crushed stone base if you need to order it too.
Asphalt formula
volume (cu ft) = area (sq ft) × thickness (in) ÷ 12
tons = volume × 145 lb ÷ 2,000
Compacted hot mix asphalt weighs about 145 lb per cubic foot, or roughly 1.96 tons per cubic yard. That works out to about 0.006 tons per square foot for each inch of thickness, so a quick rule is: tons ≈ square feet × inches × 0.006.
Tons of asphalt by driveway size
| Driveway | Sq ft | 2 in | 3 in | 4 in |
|---|---|---|---|---|
| 10 × 20 ft | 200 | 2.4 | 3.6 | 4.8 |
| 10 × 40 ft | 400 | 4.8 | 7.3 | 9.7 |
| 12 × 50 ft | 600 | 7.3 | 10.9 | 14.5 |
| 16 × 40 ft | 640 | 7.7 | 11.6 | 15.5 |
| 20 × 20 ft | 400 | 4.8 | 7.3 | 9.7 |
| 20 × 40 ft | 800 | 9.7 | 14.5 | 19.3 |
| 24 × 24 ft | 576 | 7.0 | 10.4 | 13.9 |
| 24 × 50 ft | 1,200 | 14.5 | 21.8 | 29.0 |
How thick should asphalt be?
- Walkways and paths: 2 inches over a compacted base.
- Home driveways: 2 to 3 inches compacted, over 6 to 8 inches of crushed stone.
- Driveways for RVs, delivery trucks or heavy equipment: 4 inches or more, often in two layers.
- Overlay on old asphalt: 1.5 to 2 inches, after cracks are sealed.
Most suppliers have a minimum order, often a few tons, and price drops with volume. Hot mix has to be laid while it's hot, so small DIY patches are often easier with bagged cold patch.
Frequently asked questions
How many tons of asphalt do I need for a driveway?
Multiply square feet by thickness in inches and by 0.006. A 12 × 50 ft driveway at 3 inches is 600 × 3 × 0.006 ≈ 10.9 tons.
How much does a ton of asphalt cover?
At 2 inches thick, one ton covers about 83 sq ft. At 3 inches it covers about 55 sq ft, and at 4 inches about 41 sq ft.
How much does a cubic yard of asphalt weigh?
Compacted hot mix asphalt weighs about 3,900 lb per cubic yard, or just under 2 tons.
How thick should an asphalt driveway be?
For a home driveway, 2 to 3 inches of compacted asphalt over 6 to 8 inches of compacted crushed stone. Go thicker for heavy vehicles.