Hot Mix Asphalt Calculator 2026: HMA Tons, Density, Placement Temperature, and Lift Thickness
Hot mix asphalt compacts to 145 lb/ft³ typical, ships at 290–325°F, and places at 250–275°F. The calculator below sizes your HMA order in tons or metric tonnes, with the engineer's reference table for density, mix temp, and Marshall stability.
This page answers:
- How many tons of HMA / hot mix asphalt for my project?
- What's the right density and placement temperature?
- What does "Marshall stability" or "Superpave" mean on the spec sheet?
For mix terminology behind the calculator, read the asphalt mix design basics guide. For field placement timing, pair this page with the asphalt temperature and compaction guide.
HMA calculator
What are the key hot mix asphalt specifications?
Higher for binder-modified mixes. Lower limit prevents premature aging.
At the screed. Below 225°F compaction fails — porosity locks in.
ASTM D6927. Drops to 1,000-1,500 for residential / low traffic mixes.
Target 4% per Superpave. >7% = porous; <3% = bleeds in heat.
Of total mix weight. Surface mixes use 5.5-6.5%, base mixes 4.5-5.5%.
How to calculate hot mix asphalt tonnage (5 steps)
Tons = Length × Width × Depth(ft) × 145 ÷ 2,000 × (1 + Waste%)
= ft³ × 0.0725 × waste [shortcut at 145 lb/ft³]
≈ SY × thickness (in) × 0.054 [DOT yield shortcut]The five-step procedure used by quality contractors and state DOTs:
- Area — Length × Width in feet = SF (or SY = SF ÷ 9).
- Thickness — convert inches to feet (in ÷ 12).
- Volume — SF × thickness (ft) = ft³.
- Weight — ft³ × 145 lb/ft³ (or use mix-specific density from the HMA reference table below).
- Tons — lb ÷ 2,000 + 5–10% waste.
For shape-specific area formulas (circles, L-shapes, road segments) and the metric version, see the how to calculate asphalt tonnage guide.
Worked example — 1,200 sq ft driveway at 3 in compacted depth:
- Volume = 1,200 × 0.25 = 300 ft³
- Weight = 300 × 145 = 43,500 lb
- Tons = 43,500 ÷ 2,000 = 21.75 tons
- With 5% waste = ~22.8 tons ordered
| Mix Type | NMAS | Use Layer | Lift Thickness | Density |
|---|---|---|---|---|
| SP 9.5 / 12.5 surface | 3/8" – 1/2" | Wearing course | 1.25–1.75" | 147–149 lb/ft³ |
| SP 19 binder | 3/4" | Binder / base | 2–3" | 145–147 lb/ft³ |
| SP 25 / 37.5 base | 1" – 1.5" | Base course | 3–4.5" | 140–145 lb/ft³ |
| OGFC (porous) | 3/8" | Wearing (drains) | 1.25" | 112–120 lb/ft³ |
| SMA | 1/2" | High-traffic wear | 1.5–2" | 149–152 lb/ft³ |
| Cold Patch | 3/8" | Pothole repair | varies | 110–125 lb/ft³ |
NMAS = Nominal Maximum Aggregate Size. SP = Superpave (per AASHTO M 323). SMA = Stone Matrix Asphalt. OGFC = Open-Graded Friction Course. Mix designations vary by state DOT — confirm with your supplier ticket.
Why is placement temperature non-negotiable?
HMA depends on heat for compaction. Once mat temperature drops below 225°F, the binder stiffens and the rollers can no longer close air voids. The result is permanent porosity — water infiltrates, freeze-thaw cycles split the mix, and you get raveling within 2-3 years.
- Plant temp: 290-325°F when loaded into the haul truck
- Truck cooling rate: 1°F per minute typical (covered with insulated tarp)
- Maximum haul time: ~60 minutes; longer needs a transfer device or warm storage
- Mat temp at screed: 250-275°F minimum
- Compaction window: until 175°F for static rollers, 200°F for vibratory
This is why winter paving (ambient <50°F) is risky — heat loss accelerates and the compaction window shrinks to minutes. Most state DOTs prohibit HMA placement below 40°F ambient.
Superpave vs Marshall: which spec applies?
Most U.S. state DOTs migrated to Superpave volumetric design in the 1990s-2000s. Marshall stability (ASTM D6927) is still referenced in:
- Older municipal specifications and small-town public works contracts
- Some private commercial paving (parking lots, storage yards)
- Air Force / FAA airfield mixes (uses 75-blow Marshall)
- Many Caribbean, Latin American, and Asian markets
If you see a Superpave designation (PG 64-22, SP 12.5), the mix design is volumetric. If you see Marshall stability + flow, it's the older empirical method. Both produce serviceable HMA — just different test methods.
The FAQ below answers the questions that come up when you're ordering HMA from a plant for the first time.
Hot mix asphalt FAQ
What is hot mix asphalt (HMA)?
HMA is aggregate (stone, sand, mineral filler) coated with hot petroleum-based asphalt binder, mixed at 300-325°F at the plant and placed at 250-275°F. It compacts to 145 lb/ft³ typical density and forms the dominant pavement material in U.S. road and driveway construction.
What's the placement temperature for HMA?
Mat temperature at the screed should be 250-275°F. Mix arrives from the plant at 290-325°F and cools en route. Below 225°F mat temp, compaction fails. State DOTs typically prohibit placement below 40°F ambient.
What's the density of HMA?
Standard compacted density is 145 lb/ft³ (NAPA average). Range is 140-150 depending on aggregate gradation and binder content. SMA and high-stability mixes hit 149-152 lb/ft³; OGFC and porous mixes drop to 112-120 lb/ft³.
How many tons of HMA per cubic yard?
1.96 short tons per cubic yard at 145 lb/ft³ compacted. Use 1.95-2.05 tons/CY as a working range. Loose pre-compaction volume runs 15-20% higher — that's why suppliers price by weight, not volume.
What's Marshall stability?
Marshall stability (ASTM D6927) measures HMA resistance to deformation under load. Heavy traffic surface mix needs 1,800+ lb stability with 13-20 flow units. Lower-traffic mixes meet 1,000-1,500 lb. Most state DOTs now use Superpave instead, but Marshall still appears on residential and small commercial plans.
Hot mix vs cold mix: when do I use each?
Hot mix is the primary structural material — driveways, lots, roads. Cold mix (cold patch) is a temporary winter pothole repair: stays flexible at 0°F but doesn't bond as a structural material. Use cold patch for emergency repairs only; replace with HMA when weather allows.
What's "air voids" and why does 4% matter?
Air voids are the percentage of empty space in the compacted mix. Superpave targets 4% (range 3-5%). Above 7%, water infiltrates and accelerates failure. Below 3%, the mix bleeds binder in summer heat and ruts under truck loads. Density and air voids are inversely related.