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Gravel Cubic Metre Calculator

Accurately estimate bulk crushed stone and gravel volume in cubic metres (m³) and instantly convert to quarry weighbridge tonnes (t). Includes mechanical roller compaction allowance.

Gravel & Crushed Aggregate Volume & Tonnage

Real-time volumetric & tonnage modeling (SABS & ISO Metric SI compliant)

Standard residential concrete slabs are typically 100 mm to 150 mm thick.

2.40 t/m³ (2,400 kg/m³)
+12%
0% (Exact void)+5%+10% (Recommended)+15%+25% (Excavation)
Gross Volume (Order Quantity)Live Calc
8.250m³

Includes +10% waste over net physical volume.

Net Physical Void7.500m³
Total Liquid Volume8,250L
Total Weight (t)19.80tonnes
Ready-Mix Deliveries~1.4trucks (6m³)
Imperial EquivalentsUS Customary
Cubic Yards: 10.79 yd³
Cubic Feet: 291.35 ft³
Mathematical Derivation & Proof
SI Metric Model

Formula: V_net = Length × Width × Depth

V_net = 10.000 m × 5.000 m × 0.150 m = 7.500 m³

1. Normalizing inputs to metres: L = 10.000 m, W = 5.000 m, D = 0.150 m
2. Net volume: 10.000 × 5.000 × 0.150 = 7.500 m³
3. Factoring +10% waste allowance: 7.500 × 1.10 = 8.250 m³
4. Total mass @ 2.40 t/m³ (Concrete): 8.250 × 2.40 = 19.80 tonnes
5. Standard 6 m³ truckloads: 8.250 / 6 = ~1.4 loads (order 2 trucks)

How Gravel Volume to Tonnage Conversion Works

The engineering mathematics behind volumetric measurement, compaction allowances, and ready-mix batching.

01

Normalize to Metres (m)

Slab thickness and trench depths are commonly specified in millimetres (e.g., 150 mm) or centimetres (15 cm). Convert all dimensions to metres before multiplying:

Depth (m) = mm ÷ 1,000
150 mm ÷ 1,000 = 0.150 m
02

Solve Net Volume (m³)

Multiply length by width and depth to determine the net physical void space. For cylinders (round tanks, circular slabs), multiply base area ($\pi r^2$) by height:

V_net = L × W × D
10.0 m × 5.0 m × 0.15 m = 7.50 m³
03

Apply Compaction & Waste

Excavated subgrades settle, formwork flexes under hydraulic pressure, and pumps retain residual mix. Always factor 5% to 15% extra for realistic batching:

V_order = V_net × (1 + Waste %)
7.50 m³ × 1.10 (+10%) = 8.25 m³

Gravel & Aggregate FAQs

Common questions regarding metric cubic metre calculations, bulk densities, and material batching.

How do you calculate gravel in cubic metres?
Measure your driveway or pathway area in square metres (Length × Width) and multiply by the gravel depth in metres. For a 50 mm layer over a 40 m² driveway: 40 m² × 0.05 m = 2.0 m³ of gravel.
How do I convert cubic metres of gravel into tonnes?
Multiply your cubic metres by the material density factor (approximately 1.68 tonnes per m³ for 19 mm crushed aggregate). For 2.0 m³ of gravel: 2.0 m³ × 1.68 = 3.36 metric tonnes to order from the quarry.
How thick should gravel be for a residential driveway?
A standard residential gravel driveway requires a compacted depth of 75 mm to 100 mm (0.075 m to 0.10 m). Thinner layers reveal the underlying geotextile membrane, while thicker layers cause vehicle tires to sink.
How much does gravel compact after rolling?
Crushed stone and G5 road gravel compact by approximately 12% to 15% when compacted with a vibrating plate or roller. Always add a 12% to 15% allowance to your order volume.