Asphalt Calculator
Estimate tons or tonnes of hot mix asphalt from paving area, compacted thickness and density (145 lb/ft³ typical), with truckloads, spread rate and cost.
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About this toolWhat is the Asphalt Calculator?
Hot mix asphalt is ordered by weight, but a driveway is designed by area and thickness. To get from one to the other you multiply area by compacted thickness to get volume, then by the in-place density of the mix. At the common figure of 145 pounds per cubic foot, a 50 x 12 ft driveway paved 3 inches thick takes about 11 short tons with a small waste allowance.
This calculator handles rectangles, circles, triangles, trapezoids or a known area, in feet and inches or metres and millimetres. The density field is editable because mixes differ: dense-graded surface mixes are typically 140 to 150 lb/ft³ (about 2,240 to 2,400 kg/m³) once compacted. You get short tons and tonnes, compacted volume, the spread rate in pounds per square yard per inch, the number of truckloads and the material cost.
A small table shows how the tonnage changes for other common thicknesses, which is often the quickest way to see what an extra half inch of surface course costs.
- Rectangle, circle, triangle, trapezoid or known area
- Editable compacted density with typical ranges for hot mix
- Short tons and metric tonnes with automatic price conversion
- Spread rate, truckloads and a thickness comparison table
- Copy, share link and reset; nothing leaves your browser
How to use the Asphalt Calculator
- Choose imperial or metric and the shape of the area to pave.
- Enter the dimensions, or pick Known area and type the area from a site plan.
- Enter the compacted thickness and check the density against your supplier's mix data.
- Add a waste allowance for edges, low spots and handwork, usually 3 to 10%.
- Enter the price per ton or tonne and the truck capacity to see cost and loads, then copy the result.
Worked examples
Single-car driveway
Input
50 x 12 ft, 3 in compacted, 145 lb/ft³, 5% extra
Output
11.42 short tons (10.36 t), one 15 ton truck, $1,256 at $110 per ton
Volume is 600 x 0.25 = 150 ft³. At 145 lb/ft³ that is 21,750 lb, or 22,838 lb with waste.
Cul-de-sac overlay
Input
Circle 40 ft diameter, 2 in, 145 lb/ft³, 5% extra
Output
15.94 short tons over 1,257 ft²
A circle's area is pi x d² / 4, so doubling the diameter quadruples the tonnage.
Metric car park patch
Input
200 m², 50 mm, 2,320 kg/m³, 5% extra
Output
24.36 t
10 m³ of compacted mat at 2,320 kg/m³ is 23.2 t before the allowance.
Background and insight
Asphalt plants and agency specifications describe placement as a spread rate. At 145 lb/ft³, one square yard one inch thick is 9 x (1/12) x 145 = 108.75 lb, which is why estimators use about 110 lb per square yard per inch. The same rule in metric is about 23 kg per square metre for each 10 mm. Compacted density, not the loose density in the truck, is what matters: the paver lays the mat loose and the rollers compact it by roughly 20 to 25% in thickness to reach the target air voids, typically around 7% in place for dense-graded mixes.
US suppliers quote short tons of 2,000 lb; most other countries use metric tonnes of 1,000 kg, and 1 tonne is 1.102 short tons. The calculator converts the price and truck capacity when you switch units so a quote stays comparable. Residential driveways are commonly 2 to 3 in (50 to 75 mm) of surface course on a compacted aggregate base; parking lots and roads carrying trucks need a pavement design, for example by the AASHTO method.
Common use cases
Driveway quotes
Check that a contractor's tonnage matches the area and thickness they propose.
Patching and overlays
Order the right amount of hot mix or cold patch for potholes and trench reinstatement.
Parking lots and site roads
Compare a 2 in and a 3 in surface course in tonnage and cost.
Trucking plans
Work out how many loads to schedule so the paver is never waiting for material.
Tips and limitations
- Use the compacted density from the mix design. Open-graded and porous mixes are lighter, and some heavy aggregates make mixes denser.
- The thickness here is compacted thickness. Loose mat thickness behind the paver is about 1.25 times greater.
- Low spots and an uneven base swallow material. Allow more waste on an old surface than on a fresh graded base.
- Many plants have minimum orders and small-load charges, so a 3 ton job can cost nearly as much as a 6 ton one.
Frequently asked questions
How many tons of asphalt do I need for a driveway?
Multiply the area in square feet by the thickness in feet and by 145 lb/ft³, then divide by 2,000. A 600 ft² driveway at 3 in needs 600 x 0.25 x 145 / 2,000 = 10.9 tons, about 11.4 with 5% extra.
How much does a ton of asphalt cover?
At 145 lb/ft³, one short ton covers about 83 ft² at 2 in thick, 55 ft² at 3 in and 41 ft² at 4 in. In metric, a tonne covers about 8.6 m² at 50 mm.
What is the density of compacted asphalt?
Dense-graded hot mix asphalt is typically 140 to 150 lb/ft³ (2,240 to 2,400 kg/m³) once compacted, and 145 lb/ft³ is the usual estimating figure. Use the bulk specific gravity from your supplier's mix design for accurate work.
How thick should an asphalt driveway be?
Commonly 2 to 3 in (50 to 75 mm) of compacted surface course over 4 to 8 in of compacted aggregate base for cars. Heavier vehicles, soft subgrade or cold climates call for more; a local paving contractor or engineer should confirm.
What is 110 lb per square yard per inch?
It is the spread rate of asphalt at about 145 to 147 lb/ft³: a square yard one inch thick holds 0.75 ft³. Multiply 110 by the area in square yards and the thickness in inches, then divide by 2,000 for tons.
Is a ton of asphalt the same as a tonne?
No. A US short ton is 2,000 lb (907 kg); a metric tonne is 1,000 kg (2,205 lb). A quote per tonne looks about 10% higher than the same price per short ton.
Is there an in-depth guide to the Asphalt Calculator?
Yes. “Asphalt Tonnage: From Square Feet and Inches to Tons of Hot Mix” covers the background, how it works, common pitfalls and worked examples. Read the full guide.
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