How the Gravel Calculator Works
The calculator uses three measurements to find how much material you need:
Volume = Length × Width × Depth
Weight = Volume × Density
Cost = Weight (in tonnes) × Price per tonne
All calculations happen in metric units internally. When you switch to Imperial, values are converted and results are shown in cubic yards, short tons, and pounds.
How to Use the Calculator
- Choose your unit system — Metric (m, cm, tonnes) or Imperial (ft, in, short tons).
- Enter the length and width of the area to cover.
- Enter the depth — how thick the gravel layer should be. Driveways typically need 10–15 cm (4–6 in); paths 5 cm (2 in).
- Select the material type — density fills in automatically. Choose Custom to enter your own value.
- Optionally enter a price per tonne — total cost appears instantly.
Recommended Gravel Depth by Application
| Application | Recommended Depth |
|---|---|
| Decorative garden path | 3–5 cm (1–2 in) |
| Lawn or flowerbed border | 5–7 cm (2–3 in) |
| Pedestrian path | 5–8 cm (2–3 in) |
| Driveway (light vehicles) | 10–15 cm (4–6 in) |
| Driveway (heavy vehicles) | 15–20 cm (6–8 in) |
| French drain base layer | 20–30 cm (8–12 in) |
Material Density Reference
| Material | Density (kg/m³) | Density (lb/ft³) |
|---|---|---|
| Gravel (dry) | 1,680 | 104.9 |
| Gravel (wet) | 2,000 | 124.9 |
| Crushed stone | 1,600 | 99.9 |
| Sand (dry) | 1,520 | 94.9 |
| Sand (wet) | 1,920 | 119.9 |
Densities are approximate bulk values. Your supplier’s material may differ by ±5–10%.
Sources
- Neville, A.M. Properties of Concrete. Pearson, 2011.
- USGS. Mineral Resources Program — Crushed Stone Statistics and Information.