Asphalt Calculator: How Many Tons of Asphalt Do I Need?

How to use the asphalt calculator

1. Measure the area. Use length × width for a straight driveway, or switch to square feet and add the pieces up. Treat flares, parking pads and turnarounds as extra rectangles and triangles.
2. Enter the compacted thickness. This is the finished thickness after rolling, the number a paving contract should state. The quick buttons cover the common cases: a 1.5–2 in overlay, 3 in of asphalt over a stone base, and 4.5 in of full-depth asphalt.
3. Check the density. The default is 145 lb per cubic foot of compacted mix. If the plant gives you a spread rate in pounds per square yard per inch, divide it by 0.75 to get lb/ft³ (110 lb/sy/in is about 147 lb/ft³).
4. Add extra. 5% is our default for edges, low spots and handwork. Use more for small, irregular or hand-raked jobs.
5. Base and price (optional). Keep the stone base on for a new driveway and turn it off for an overlay. Enter a quoted price per ton to see the cost of the mix.

How many tons of asphalt do I need? The formula

Asphalt plants sell hot mix by weight, so the job is converting a volume into tons. The weight depends on the stone, the binder content and how well the mix is rolled. The Pennsylvania Asphalt Pavement Association’s booklet, published with Penn State, puts typical compacted mix at 108–120 lb per square yard per inch, or 144–160 lb per cubic foot. Our 145 lb/ft³ default sits at the light end of that range.

Highway agencies think in square yards per inch: Michigan DOT’s manual says 110 lb per square yard equals 1 inch of thickness. One square yard at 1 inch is 0.75 cubic feet, so that is 146.7 lb/ft³, and our default (108.75 lb/sy/in) is about 1% lighter. The booklet’s own example, a 150 × 300 ft lot at 3 in, comes to 825 tons at 110 lb/sy/in. Our default gives about 816.

Worked examples

New 50 × 12 ft driveway, 3 in over 6 in of stone

50 × 12 = 600 sq ft. At 3 in that is 600 × 3 ÷ 12 = 150 cu ft. At 145 lb/ft³ the mix weighs 21,750 lb, or 10.9 tons. With 5% extra, order about 11.4 tons. The 6 in compacted base is 300 cu ft, or 11.1 cubic yards. At 1.85 tons per compacted yard that is about 20.6 tons of crushed stone, which is roughly 13.9 loose yards on the truck. If the plant quotes $110 a ton, the mix alone is about 11.4 × 110 = $1,256. That is only an illustration; your price will differ.

Overlay on a 24 × 20 ft two-car pad, 2 in

480 sq ft × 2 ÷ 12 = 80 cu ft, which is 11,600 lb or 5.8 tons. With 5% extra, order about 6.1 tons. No new base is needed, so turn the base option off. Before the overlay, the contractor should cut out and patch weak spots and apply a tack coat so the new layer bonds.

Pothole patch, 4 × 3 ft, 2 in deep

12 sq ft × 2 ÷ 12 = 2 cu ft, which is about 290 lb of hot mix (0.15 tons). Many plants have a minimum load, so a patch this small is often done with bagged cold patch instead. Check the coverage printed on the bag.

Asphalt driveway thickness and base

There are two common ways to build a residential asphalt driveway. One is asphalt over a compacted crushed-stone base. The other is full-depth asphalt, which goes straight onto the prepared soil. The Colorado Asphalt Pavement Association’s driveway brief gives these minimums for cars, light trucks and the occasional delivery truck:

An Asphalt Institute brief calls 6–8 in of crushed aggregate “usually adequate,” under a 2 in bottom course and a 1.5 in surface course. The Illinois Asphalt Pavement Association says 4 in of full-depth asphalt may be adequate and 5–6 in is stronger, placed in lifts. Overlays on a sound driveway are typically 1.5–2 in.

Drainage matters as much as thickness. The Colorado brief recommends sloping the surface at least ¼ in per foot. It also says to strip out topsoil and roots and compact the subgrade before any base goes down. Thickness and base depth are design decisions for your contractor and local conditions. This calculator turns whatever design you choose into an order quantity.

Compaction, waste and what the tons don’t include

• Use compacted thickness. Loose mix is laid thicker and rolled down. The density is for compacted mix, so pair it with the finished thickness.
• In-place density varies. The Pennsylvania booklet assumes rolled mix reaches about 94% of its maximum theoretical density. A poorly rolled mat weighs less but won’t last.
• Extra for waste. Uneven base, thickened edges and handwork around slabs and drains use mix you won’t see on the plan. Start at 5% for a simple rectangle and go higher for small or irregular jobs.
• Not included: tack coat, edging, sealcoat, hauling, minimum-load charges and labor. The cost line is for the mix only, at the price you enter.

The base stone uses the same figures as our paver calculator: 1.85 tons per compacted cubic yard of crushed base course and about 1.48 tons per loose yard on the truck, both from WSDOT. For other stone, or to plan truckloads of base, use the gravel calculator. If you are weighing asphalt against a poured slab, the concrete calculator gives cubic yards for the same footprint.

Tons of asphalt per 100 square feet

Sources & assumptions

How this calculator gets its numbers. Full method: our methodology.

• Tons = area × compacted thickness × density ÷ 2,000, with a default of 145 lb/ft³ of compacted mix (108.75 lb/sy/in). Use your plant's figure if you have it.
• The default 5% extra is a CalcTheJob allowance, not an industry standard. Base stone uses 1.85 tons per compacted and 1.48 per loose cubic yard.
• The cost line is your price × tons of mix only. This is a quantity estimate, not a pavement design.

Sources

1. Pennsylvania Asphalt Pavement Association / Penn State Superpave Center, Constructing Quality Asphalt Pavements checklist booklet (2025). Compacted mix typically 108–120 lb/sy/in (144–160 lb/cf); 150 × 300 ft lot at 3 in = 825 tons at 110 lb/sy/in; in-place density about 94% of maximum.
2. Michigan Department of Transportation, 501 – Plant Produced Hot Mix Asphalt (Construction Manual). Yield check rule: 110 pounds per square yard = 1 inch of thickness; application-rate table by thickness.
3. Colorado Asphalt Pavement Association, Asphalt Driveways technical brief (2020). Minimum residential designs: 4.5–5.5 in full-depth, or 3 in of asphalt over 4–6 in of aggregate base, by subgrade; surface slope at least ¼ in per foot; overlays typically 1.5–2 in.
4. Asphalt Institute (Colorado APA brief), “Best Practices” for the Use of Asphalt Driveways. 6–8 in of crushed aggregate base is usually adequate, with a 2 in bottom course and a 1.5 in surface course.
5. Illinois Asphalt Pavement Association, Driveways. 4 in of full-depth asphalt may be adequate, 5–6 in is stronger; placing in lifts; overlays of 1.5–2 in.
6. Washington State Department of Transportation, Design Manual M 22-01, Chapter 620, Exhibit 620-1 (Unit Dry Weight – Gravel Base and Surfacing). Crushed surfacing base course: 2,950 lb/cy (1.48 T/cy) truck measure, 3,700 lb/cy (1.85 T/cy) compacted.

Last reviewed October 25, 2026. Product figures vary by brand; the label on what you buy wins.