How to use this calculator
- 1Measure the length and width of the driveway or path, or enter the area if you already know it.
- 2Enter the compacted thickness of asphalt you want. 2–3 inches (50–75 mm) is common for home driveways.
- 3Keep the typical density, or type the figure from your asphalt plant.
- 4Keep 5 % extra for an uneven base and the edges, or change it.
- 5Read off the tonnes or US tons to order, and the volume.
The formula
- 01Volume = area × compacted thickness × (1 + extra %)
- 02Weight = volume × density
- 03Rule of thumb: 110 lb per square yard per inch of thickness (1.98 US tons per yd³ ≈ 2.35 t/m³)
Asphalt is bought by weight, but you measure an area and a thickness, so the density links the two. The Asphalt Institute's rule of thumb is 110 lb for every square yard of asphalt 1 inch thick. That is 1.98 US tons per cubic yard, about 147 lb/ft³ or 2.35 t/m³, and it is what the calculator uses. Many estimators use 145 lb/ft³ (about 2.32 t/m³), which gives a slightly lower weight; your asphalt plant can give you the figure for its mix.
The thickness is the compacted thickness. Loose asphalt from the truck is spread thicker and rolled down, so always work with the finished figure. UK driveways are usually built in two layers, a binder course of about 50 mm and a surface course of about 20–25 mm, so enter the total or work out each layer on its own.
Some asphalt is always lost to an uneven base, tapered edges, hand work and what stays in the truck, so the calculator adds 5 % by default. That is the top of the 3–5 % that paving estimators commonly carry; add more for small hand-laid jobs.
Worked example
A 40 ft × 12 ft driveway (480 ft²) paved 3 in thick needs 8.8 tons of asphalt at 1.98 tons/yd³.
With 5% extra for an uneven base and edges, order about 9.24 tons (4.67 yd³).
Tips before you buy
- Check the base before paving: soft spots, standing water or a thin base will show through any asphalt surface within a few years.
- Ask each contractor to write the compacted thickness of asphalt and the depth of the gravel base on the quote, not just the price.
- Make sure the finished surface slopes so rain runs off it and away from the house or garage.
- Keep the delivery tickets from the asphalt plant: they show how many tons were actually delivered for your job.
- Resurfacing over old asphalt? Measure the thickness of the new layer only.
Frequently asked questions
How many tons of asphalt do I need for a driveway?
Multiply the area by the compacted thickness and the density. As a rule of thumb, each square yard (9 ft²) of asphalt 1 inch thick weighs about 110 lb, so a 480 ft² driveway paved 3 in thick needs about 8.8 US tons, plus a few percent extra.
How thick should an asphalt driveway be?
The Illinois Asphalt Pavement Association says many contractors use about 3 in of asphalt over 6–8 in of compacted gravel, or 4–6 in of full-depth asphalt. UK driveways usually have a 40–50 mm binder course and a 20–25 mm surface course over at least 100 mm of sub-base.
How much does a cubic yard of asphalt weigh?
About 1.98 US tons (3,960 lb) using the 110 lb per square yard per inch rule, and a cubic metre about 2.35 tonnes. With the 145 lb/ft³ figure many estimators use, a cubic yard weighs about 1.96 tons.
How much area does a ton of asphalt cover?
At 110 lb per square yard per inch, one US ton covers about 164 ft² at 1 inch thick, 82 ft² at 2 inches and 55 ft² at 3 inches. A tonne covers about 17 m² at 25 mm or 5.7 m² at 75 mm.
Is tarmac the same as asphalt?
In everyday British English, “tarmac” means a road or driveway surface of stone bound with bitumen, which Americans call asphalt or blacktop. For estimating it makes no difference: both are bought by weight and the calculator works the same way.
How much extra asphalt should I order?
A little. Paving estimators often carry 3–5 % for uneven edges, hand work and truck-to-truck differences. The calculator starts at 5 %; add more for small, hand-laid jobs or a very uneven base.
Also searched as: asphalt tonnage calculatortarmac calculatorhow much asphalt do I needasphalt driveway calculatorblacktop calculatorhot mix asphalt calculator
Sources
- Asphalt Institute, Asphalt magazine – Five rules of thumb (110 lb per yd² per inch)
- Illinois Asphalt Pavement Association – Asphalt driveways (thickness and base)
- Pavingexpert – Tarmacadam construction layers (UK binder and surface courses)
- OneCrew – How to calculate asphalt tonnage (145 lb/ft³; 3–5 % extra)
Formulas last reviewed: September 30, 2026 ·How we check our formulas