Professional bitumen and aggregate estimation using SI metric units — m², mm, kg/m³, and tonnes. Suitable for European, Australian, New Zealand, and African projects.
Length in metres (m) or kilometres (km), thickness in millimetres (mm), density in kg/m³. Output in metric tonnes (t) and cubic metres (m³).
Suitable for projects following European EN standards, Austroads, NZTA, SATCC (Africa), and other metric-based design specifications.
1 tonne = 1,000 kg. 1 m³ ≈ 2.3 t for standard dense HMA. Use the Measurement Converter for imperial conversions.
Enter dimensions to calculate
Typical bitumen content and density values for common metric pavement mixes.
| Mix Type | Bitumen Content (%) | Density (kg/m³) | Typical Application |
|---|---|---|---|
| Dense-Graded AC 14 | 5.0–6.0 | 2300–2400 | Wearing/intermediate course |
| Dense-Graded AC 20 | 4.5–5.5 | 2300–2400 | Binder / base course |
| SMA 11 / SMA 14 | 6.0–7.5 | 2250–2350 | High-traffic wearing course |
| OGFC / Porous AC | 5.5–6.5 | 1900–2100 | Noise reducing, drainage |
| WMA (Warm Mix) | 5.0–6.0 | 2280–2380 | Reduced temp paving |
| RAP Overlay | 4.0–5.5 | 2200–2300 | Recycled overlay |
The SI metric formula works entirely in metres, millimetres, and kilograms — no imperial conversions needed. Output is in metric tonnes, the standard procurement unit in Australia, New Zealand, Europe, and most of Africa and Asia.
A 2 km urban road, 7 m wide, receiving a 50 mm AC 14 wearing course at 2,350 kg/m³. Weight = 2,000 m × 7 m × 50 mm ÷ 1,000 × 2,350 ÷ 1,000 = 1,645 tonnes. At typical 25-tonne truck payloads, this requires 66 truck loads. Add 5% waste = order 1,727 tonnes.
Metric mix densities vary significantly by type: Dense-graded AC — 2,250–2,400 kg/m³; SMA 11/SMA 14 — 2,250–2,350 kg/m³; OGFC/Porous AC — 1,900–2,100 kg/m³; WMA (warm mix) — 2,280–2,380 kg/m³. Always use the certified compacted density from your plant's mix design. Using the wrong density can cause a 10–20% ordering error on large metric projects.
A useful site check: kg/m² = Thickness (mm) × Density (kg/m³) ÷ 1,000. For 50 mm at 2,350 kg/m³: 50 × 2,350 ÷ 1,000 = 117.5 kg/m². Divide by 1,000 to get tonnes/m². This rule lets supervisors cross-check delivery dockets against site records instantly. For US imperial projects, use the Square Feet Calculator.
This calculator suits projects following Austroads (Australia/NZ), EN 13108 (Europe), SATCC (southern Africa), and JTGE20 (China). For projects specifying area in m² directly, use the Square Metres Calculator. For unit conversion between imperial and metric, use the Measurement Converter.
From international road authorities to project engineers on European-standard contracts — this is the go-to tool for asphalt estimation in SI metric units.
Civil engineers working on projects under EN 13108, Austroads, or SATCC specifications calculate asphalt tonnage entirely in SI units. This calculator handles m, mm, and kg/m³ natively — no conversions from imperial required. Bill of Quantities (BOQ) items on international contracts are always in metric tonnes, so this tool produces output that feeds directly into tender documents and procurement schedules without unit reconciliation errors.
Related: Square Metres Calculator
QS professionals preparing Bills of Quantities for infrastructure projects need accurate metric tonnage for asphalt work packages. This calculator provides both total mix weight and bitumen/aggregate sub-quantities, enabling direct population of BOQ line items. Cost plans for road projects at early design stage typically use kg/m² unit rates derived from this type of calculation — enter design dimensions and read off the tonnes to apply your cost rate.
Related: Asphalt Cost Calculator
On-site engineers verify that delivered asphalt tonnage corresponds to the specified design thickness and area. By back-calculating thickness from delivered tonnes (using the Thickness Calculator) or forward-checking using this metric calculator, supervisors can flag under-delivery before the crew moves off-site. This QC check is standard practice on Austroads and European NRA contracts where layer thickness tolerances are tightly specified (typically ±5 mm).
Related: Thickness Calculator
More metric and international pavement tools.
Input area in square metres (m²) or length × width in metres. For thickness, use millimetres (mm) — the most common unit in metric asphalt specifications such as those used in Australia (Austroads), New Zealand (NZTA), the UK, and most of Europe. The calculator accepts decimal values for precision.
Dense-graded asphalt concrete typically compacts to 2.30–2.40 t/m³. Open-graded friction course (OGFC) mixes run lighter at around 2.10–2.20 t/m³, while stone matrix asphalt (SMA) is typically 2.35–2.45 t/m³. Use your mix design document for the most accurate bulk specific gravity value.
The output is in metric tonnes (t), which is the standard for asphalt procurement in countries using SI units. Cross-reference the result with your contractor's quote. For large projects, also calculate the number of truck loads needed by dividing total tonnes by your tipper's payload capacity (typically 20–25 t per load).
A metric tonne (t) equals 1,000 kg or approximately 2,205 lb. A US short ton is 2,000 lb (907 kg), and a UK long ton is 2,240 lb (1,016 kg). When purchasing asphalt in Australia, New Zealand, or Europe, quotes are in metric tonnes. In the United States, short tons are standard. Always clarify the unit with your supplier — a 10% difference in unit interpretation can significantly affect project cost.
This calculator works for any asphalt concrete (AC) mix specified by thickness and density in metric units, including Austroads AC 14, AC 10, and AC 7 mixes (Australia/NZ), EN 13108 asphalt concrete (Europe), and DBM/HRA (UK). It is not intended for sprayed bituminous seals or slurry surfacings, which are quantified by area and application rate rather than volume and density.
For planning and budgeting, online calculators are accurate to within 5–10% when you use the correct density and compacted thickness. Real-world variation comes from surface irregularities in the subbase, edge thickening, and mix delivery tolerances. Contractors typically order 5–10% extra material to account for these factors. Get a formal quantity survey from your paving contractor before finalising orders on projects over 500 m².
Yes — running your own estimate is a practical way to sense-check a quote. Enter the agreed area, layer thickness, and density, and compare your tonnage figure with what the contractor has quoted. If the figures differ by more than 10–15%, ask the contractor to walk you through their calculation method. Discrepancies sometimes indicate a different density assumption or a different interpretation of the paving area boundaries.
Under Austroads specifications, dense-graded asphalt concrete (AC) typically compacts to 2,300–2,400 kg/m³ depending on aggregate type and gradation. The most commonly used default for estimating purposes is 2,350 kg/m³. NZTA specifications use similar values. For budgeting, 2,300 kg/m³ is a conservative value that slightly over-estimates tonnage — useful when you want to ensure you order enough. Always request the certified compacted density from your plant's mix design report for final procurement quantities on projects over 500 m².
At 50 mm thickness and 2,350 kg/m³ density: 1,000 × 0.050 × 2,350 = 117,500 kg = 117.5 metric tonnes. At typical 25-tonne tipper payload: 117.5 ÷ 25 = 4.7 loads → order 5 full loads (125 tonnes). For a 20-tonne payload: 6 loads. Always add 5% overage = 123.4 tonnes total. Confirm the plant's truck payload and whether they can do partial loads (many plants have a 25-tonne minimum delivery for HMA). Use the Asphalt Cost Calculator to price the total order.
In the Austroads/NZTA system (and broadly in EN 13108), the number refers to the nominal maximum aggregate size (NMAS) in millimetres. AC 10 = 10 mm max aggregate, AC 14 = 14 mm, AC 20 = 20 mm. Finer mixes (AC 10) are used for thin wearing courses providing a smooth surface; coarser mixes (AC 20) are used for binder and base courses carrying structural load. For surface courses receiving pedestrian or light traffic, AC 10 at 25–35 mm thickness is typical; for urban arterials, AC 14 at 40–50 mm is standard; for base courses, AC 20 at 70–100 mm. Each designation also has sub-classes (e.g., AC 14 dense graded, AC 14 open graded) with different bitumen content and density values.