Field calculator

Asphalt tonnage calculator

Enter the length and width in feet, the compacted thickness in inches, and the mix unit weight (compacted hot-mix asphalt runs about 145 to 150 lb per cubic foot, so 145 is the default). The calculator returns the tons to order and a 10 percent allowance for waste, joints, and yield. Confirm the unit weight and the final order with the asphalt plant.

Worked example

A parking lot is 100 ft × 50 ft, paved 3 in thick with hot-mix at 145 lb/cu ft.

Area100 ft × 50 ft
Compacted thickness3 in
Unit weight145 pcf

Volume = 100 × 50 × (3 ÷ 12) = 1,250 cu ft.
Tons = volume × unit weight ÷ 2,000 = 1,250 × 145 ÷ 2,000 = 90.6 tons.
With 10% for waste and compaction variation: about 99.7 tons.

Order about 90.6 tons of mix (roughly 99.7 with a 10% cushion). Confirm the mix unit weight with the plant.

Change the numbers in the calculator above to run your own.

anvilfield.com/calculators/asphalt-tonnage-calculator · Free field calculators and FieldOS. A planning estimate, verify against the code, the manufacturer, and the engineer of record.

More Paving calculators

Aggregate base calculatorFind the tons of crushed aggregate base for a given area and compacted depth.Asphalt density calculatorTurn a mat density reading and the Gmm into % Gmm and air voids, and check it against the acceptance target before the lot cools.Soil swell/shrink calculatorConvert earthwork volume between bank, loose (haul), and compacted using swell and shrink: loose = bank x (1+swell), compacted = bank x (1-shrink).Trench volume calculatorFind excavation volume: length x width x depth in feet, divided by 27 for cubic yards, plus an approximate truck-load count.

Comparing your options?

Permeable vs conventional pavementPermeable pavement stores and infiltrates stormwater; conventional pavement carries load and sheds water. The site's drainage need and traffic decide it.

Asphalt tonnage FAQ

How thick should asphalt be?

Asphalt thickness depends on the traffic and the subgrade, so there is no single number. A car-only parking lot can run a couple of inches over modest base, while a truck route over soft soil needs a full structural design. Size it to the design ESALs and the subgrade strength using the agency method, never by habit.

What is an ESAL?

An ESAL, an equivalent single axle load, is the damage done by one pass of a standard 18,000 lb single axle on dual tires. Pavement design counts ESALs, not vehicles, because damage rises with about the fourth power of axle load. Trucks do nearly all of it, so the design is sized to the trucks, not the cars.

What is a structural number?

A structural number, SN, is the total structural strength AASHTO 93 says a flexible section needs over a given subgrade for the design traffic. It is not a thickness. The design distributes the required SN across layers using each layer's thickness and its layer coefficient, so several different sections can satisfy the same SN.

How does the subgrade affect pavement thickness?

The subgrade sets how thick the section must be, because it is the foundation everything rests on. A stiff subgrade spreads load well and lets the layers be thinner; a soft subgrade deflects and forces a thicker, stronger section. The geotech reports the strength as resilient modulus, CBR, or R-value, and that value sizes the section above it.

AASHTO 93 vs Pavement ME: which design method do I use?

Use the method the owner and jurisdiction require. AASHTO 93 is the empirical method that produces a structural number, still common on site and local work. Pavement ME is the mechanistic-empirical successor that models layer response and predicts distress, common on agency highway design. Both are legitimate; do not mix the two on one design.

More in the Asphalt pavement thickness design field guide.