Enter your area and paving depth to get the tonnage, volume and truckloads you need — with the density we used and where it came from shown underneath.
Asphalt is ordered by weight, but most people measure their project by area. This calculator bridges the two: it turns area and compacted thickness into cubic yards, short tons and the number of truckloads, using a density figure published by a state department of transportation specifically for estimating quantities.
The tonnage figure comes from three multiplications: area times depth gives volume, a waste allowance is added, and volume times density gives weight. Because the density of asphalt varies with the mix design and how well it is compacted, we show the result as a range rather than pretending to a precision we do not have.
Most asphalt calculators show you one number and never tell you where it came from. This one prints the density, the exact source, and a worked example you can check on a pocket calculator.
A worked example you can check by hand
A 20 ft × 10 ft area at 2 in deep,
with a 5% waste allowance:
Area
200 ft² (20 ft × 10 ft)
Depth
2 in = 0.1667 ft
Volume (before waste)
33.3333 ft³
Waste allowance
5%
Volume (with waste)
35 ft³ = 1.2963 yd³
Density used
145 / 145 / 147 lb/ft³ (low / typical / high)
Weight (low)
5,075 lb = 2.5375 short tons
Weight (typical)
5,075 lb = 2.5375 short tons
Weight (high)
5,145 lb = 2.5725 short tons
How we calculate this — and every number we used
We do not use a hidden "magic number". Here is the entire calculation:
volume = area × depth
volume_with_waste = volume × (1 + waste%)
weight = volume_with_waste × density
Why a range, not one number? Bulk material density changes with
moisture, gradation and compaction. Publishing a single figure would be falsely precise, so we publish
the range our sources support — and we show you exactly where each number comes from.
Why we state the state. This material is only published at one
placement state, so there is nothing to choose — but we say which one it is, because loose and compacted
material differ by 27–60% in volume and most calculators never tell you which they used.
Asphalt — hot mix asphalt (HMA), compacted in place
How we chose the typical value. Iowa DOT lists 145 pcf for general HMA and base course, and 147 pcf for surface and intermediate courses, explicitly for estimating quantities. AASHTO LRFD independently gives 140 lb/ft³ for bituminous wearing surfaces as a structural design value. We use the estimating figure because this tool is for ordering material.
Limits of this constant
AASHTO LRFD gives 140 lb/ft³ for bituminous wearing surfaces as a structural dead-load value, while Iowa DOT gives 145 lb/ft³ explicitly 'for estimating quantities'. They differ by 3.6% and describe different purposes. Because this calculator is for ORDERING material, we use the Iowa DOT estimating figure; if you are doing structural design, use 140.
Single authoritative source. We could not retrieve NAPA, FHWA or Asphalt Institute figures, so we do not claim the 140–150 lb/ft³ spread that other calculators use.
These are compacted, in-place estimating densities — not loose stockpile density.
Not valid for high-performance thin-lift overlays (150 pcf) or slag mixes (170 pcf).
This calculator is only valid under these assumptions. If any of them do not match your project,
treat the result as a rough guide and get a quote from your supplier.
The area is treated as a rectangle. For an L-shaped or curved driveway, split it into rectangles and add the results.
Depth means the COMPACTED thickness of the finished asphalt layer, which is how asphalt is specified and how the density we use is defined. Loose material before rolling is thicker.
You are paving a single uniform layer. Multi-layer build-ups (base course plus surface course) should be calculated as separate layers at their own thicknesses.
The asphalt is conventional hot mix asphalt (HMA). High-performance thin-lift overlays and slag mixes are denser and this figure does not apply to them.
No allowance for sub-base, grading or site preparation — this calculates the asphalt only.
Frequently asked questions
How many tons of asphalt do I need per square foot?
At a typical 2 inch compacted thickness, one square foot of asphalt weighs roughly 24 pounds, so 1,000 square feet needs about 12 short tons before any waste allowance. Doubling the thickness doubles the tonnage. This calculator does that arithmetic for your exact area and depth.
What density do you use for asphalt, and why?
We use 145 lb/ft³, taken from the Iowa Department of Transportation Design Manual section that is literally titled "Densities for Use in Estimating Quantities". It is the official estimating value for hot mix asphalt and base course; the same table gives 147 lb/ft³ for surface and intermediate courses, which is why we show 145–147 as the range.
Some calculators display a wider, rounder spread around this value. We do not, because we could not retrieve an authoritative source for those two end points — so we would be inventing them.
Why is the answer a range instead of one number?
Asphalt density depends on the aggregate gradation, the binder content and above all how well the material is compacted on site. Publishing a single figure to three decimal places would be falsely precise. The range reflects what the sources actually support.
Should thickness be loose or compacted?
Compacted — the thickness of the finished, rolled surface. That is how asphalt is specified, priced and measured, and the density figure we use is defined on the same basis. If you enter a loose depth you will over-order.
Is this suitable for a commercial car park?
It gives you a good order-of-magnitude tonnage, but commercial paving is usually specified by an engineer with a mix design, layer thicknesses and compaction requirements. Use this to sanity-check a quote, not to replace the specification.