Free aggregate calculator: how much gravel, sand or crushed stone you need — volume in m³, weight in tonnes and kg, number of bags and truck loads, from a volume or area × thickness.
Approximate bulk density — multiply the volume in m³ by this figure to get tonnes:
| Material | Density (t/m³) | 1 m³ ≈ |
|---|---|---|
| Coarse sand | 1.6 | 1.6 t |
| Gravel | 1.5 | 1.5 t |
| Crushed stone | 1.5 | 1.5 t |
| Cobbles / boulders | 1.6 | 1.6 t |
| Base / sub-base | 2.0 | 2.0 t |
Volume (m³) = area (m²) × thickness (m), or enter it directly. Tonnes = volume × density (t/m³). Bags = total kg ÷ bag size; truck loads = volume ÷ truck capacity (rounded up).
Aggregate = árido = Zuschlag / Schüttgut · Gravel = grava / gravilla = Kies · Sand = arena = Sand · Crushed stone = ripio / chancado = Schotter · Cobbles = bolón = Bruchstein.
It depends on the bulk density of the aggregate. Gravel and sand are about 1.5–1.6 t/m³, so 1 m³ ≈ 1.5 tonnes. Crushed base/sub-base is denser (~1.9–2.1 t/m³). Multiply the volume by the density to get the weight.
Use the area × thickness mode: volume (m³) = area (m²) × thickness (m). For 20 m² at 15 cm that is 3 m³; multiply by the density (~1.5) for ~4.5 tonnes. Add 5–15% for compaction.
Bags = total kg ÷ bag size (e.g. 25 kg), rounded up. Truck loads = volume ÷ the truck capacity (e.g. 7 m³), rounded up. For large volumes a tipper truck is far cheaper than bags.