Asphalt Tonnage Calculator

How the asphalt tonnage formula works

Hot mix is sold by the ton, but you measure the job in square feet and inches. The calculator converts one to the other in three steps:

1. Volume: square feet × thickness in feet (inches ÷ 12) = cubic feet.
2. Weight: cubic feet × density (lb per cubic foot) = pounds.
3. Tons: pounds ÷ 2,000.

Put together:

tons = sq ft × thickness (in) × density (lb/ft³) ÷ 24,000

The 24,000 is just 12 inches per foot × 2,000 lb per ton. At the default density of 145 lb/ft³, that's:

tons = sq ft × inches × 145 ÷ 24,000

If you measure in square yards

Multiply square yards by 9 to get square feet, or use the per-yard shortcut. At 145 lb/ft³, one square yard one inch thick weighs about 109 lb (0.054 tons), so:

tons ≈ sq yd × inches × 0.0544

About the 145 lb/ft³ density

145 lb/ft³ is a rule of thumb for compacted hot-mix asphalt, not a spec. The real number depends on the mix: aggregate type, gradation, binder content and how well it's compacted. Two plants' “surface mix” won't weigh the same.

So:

• Confirm against your plant tickets. After a job, compare the tons you estimated to the tons on the tickets for the same area and depth. If you're always short, your mix is heavier than 145. If you have leftovers every time, it's lighter.
• Ask your plant for the unit weight of the mix you're buying.
• Change the density in the calculator once you know your number. Every estimate after that gets more accurate.

Add waste: how much and why

The formula gives you the asphalt that ends up compacted in place at exactly the thickness you entered. Real jobs use more:

• The base isn't perfectly flat, so low spots take extra.
• Edges get feathered, tapered and hand-worked.
• Some material stays in the truck bed, the paver hopper or the wheelbarrow.
• Thickness is compacted thickness. If you're thinking in loose depth behind the screed, you'll come up short.

A common allowance is 5–10% waste. Use the low end on a clean overlay of a large, even lot, and the high end on small jobs, patches and anything with a lot of handwork. Your plant tickets will tell you where your crew actually lands.

Worked examples

Examples only. Plug in your own measurements, density and waste.

Residential driveway

12 ft × 50 ft = 600 sq ft at 2 in compacted
600 × 2 × 145 ÷ 24,000 = 7.25 tons
+7% waste = 7.76 → order 8 tons

Larger driveway or small lot

1,500 sq ft at 3 in
1,500 × 3 × 145 ÷ 24,000 = 27.19 tons
+10% waste = 29.9 tons

Parking lot overlay

20,000 sq ft at 1.5 in
20,000 × 1.5 × 145 ÷ 24,000 = 181.25 tons
+5% waste = 190.3 tons

Turning tons into truckloads

Divide total tons by the legal payload of the trucks hauling it, and round up. Payload depends on the truck and your state's weight limits, so use your own number.

What about base, gravel and sand?

The formula is the same. Only the density changes. Base, gravel, decomposed granite and sand all weigh different amounts per cubic foot, and the number changes with moisture and compaction. Get the density from your supplier, put it in the density box, and the math holds.

Common mistakes

• Mixing up loose and compacted depth. The formula uses compacted thickness.
• Forgetting waste, then running out with 200 sq ft left to pave.
• Using one density forever. Calibrate it to your plant's tickets.
• Pricing only the tons. Tonnage is material. The bid also needs tack, base work, labor, trucking, equipment, overhead and your margin: cost everything, then price with margin, not markup.

Do this math inside your estimates

In , any estimate line billed by the ton does this calculation for you. Enter the area and lift thickness and the tons fill in. Pick hot mix, flex base, gravel, decomposed granite or sand, and each comes with a rule-of-thumb density you can check against your supplier. You can type over the tons whenever your tickets say otherwise.

Even faster: trace the lot on aerial imagery with Measure (Crew plan and up). You get square feet and an estimated tonnage for each shape, and Use in New Estimate turns it into a priced bid you can text to the customer.

See pricing, or start free, 14 days, no card →

Doing maintenance work too? Try the sealcoating calculator.

Related: how to bid sealcoating jobs, sealcoating software and asphalt paving estimating software.

FAQ

How many tons of asphalt do I need?

Multiply square feet × compacted thickness in inches × 145, then divide by 24,000. Add 5–10% for waste. Example: 600 sq ft at 2 in = 7.25 tons, about 7.8 with 7% waste.

How much does a ton of asphalt cover?

At 145 lb/ft³, one ton covers about 166 sq ft at 1 in compacted, 83 sq ft at 2 in, or 55 sq ft at 3 in. Your mix's real density will move those numbers.

How many tons of asphalt per square yard?

About 0.054 tons (roughly 109 lb) per square yard per inch of compacted thickness at 145 lb/ft³. Multiply by your thickness in inches.

What density should I use for hot-mix asphalt?

145 lb/ft³ is a common rule of thumb for compacted hot mix. Confirm it against your plant's tickets or ask the plant for the unit weight of your mix.

How much waste should I add for asphalt?

5–10% is a common allowance. Use more on small, hand-worked jobs and patches, and less on large, even overlays. Track your tickets to find your crew's real number.

Is the thickness loose or compacted?

Compacted. If you're thinking in loose depth behind the paver, the estimate will come up short.