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Gravel Calculator
Tonnes / cubic yards of gravel for driveway, French drain or path.
Formula
tonnes = yd³ × density_t/yd³
How to use
- 1Measure the area length and width in feet.
- 2Pick a depth: ~4 in for a path, 6-8 in for a driveway base, 2-3 in for top dressing.
- 3Choose the gravel type to set the density.
- 4Read tonnes, cubic yards and cubic metres, then add ~10% for compaction.
About this calculator
Order too little gravel and the job stalls; order too much and you pay to haul away the surplus. This calculator turns three measurements and a gravel type into both a volume and a weight, so you can order in whichever unit your supplier uses - tonnes or cubic yards.
Formula explained
Volume (yd³) = Area (ft²) × Depth (in) ÷ 324. The 324 converts square-feet-times-inches into cubic yards in one step. Tonnes = Volume × Density, where density varies by stone: crushed 1.4 t/yd³, pea 1.35, river rock 1.3, limestone 1.45. Multiply tonnes by 1.10231 for US tons.
Worked example
300 ft² × 4 in ÷ 324 ≈ 3.7 yd³. × 1.4 ≈ 5.18 tonnes, about 5.71 US tons.
Tips & notes
- Match depth to the job rather than defaulting to a single number - depth is where most ordering errors start.
- Confirm the density with your supplier, since local stone varies.
- Ask whether they sell by weight or volume, and quote them that figure.
- Add about 10% for compaction, spillage and uneven ground.