How this is calculated
Like concrete, gravel volume is length × width × depth. Because gravel is priced and delivered by weight rather than volume in most of the US and UK, this calculator converts the volume to an estimated tonnage using a typical compacted-gravel density.
Density varies by material — crushed limestone, pea gravel, and river rock all settle differently — so the weight shown here is a planning estimate. Your supplier can give an exact figure for the specific material you're ordering.
Formula & methodology
Volume = Length × Width × Depth. Weight (US tons) ≈ Volume (yd³) × 1.4. Weight (tonnes) ≈ Volume (m³) × 1.6.
Worked example
A 20 ft × 3 ft path, 3 in deep
- 1.Convert depth to feet: 3 in ÷ 12 = 0.25 ft
- 2.Volume = 20 ft × 3 ft × 0.25 ft = 15 ft³
- 3.Cubic yards = 15 ÷ 27 = 0.56 yd³
- 4.Estimated weight = 0.56 × 1.4 ≈ 0.78 tons
Frequently asked questions
How deep should a gravel driveway be?
A single-layer gravel driveway is typically 4 inches (10 cm) deep; a full sub-base-and-topping build can run 6–8 inches (15–20 cm) across two layers.
Why does the calculator show weight instead of just volume?
Most gravel suppliers quote and deliver by the ton, not the cubic yard, so a weight estimate is more directly useful for ordering — the volume is shown too so you can sanity-check it.
Does gravel need compacting before I add a top layer?
Yes for driveways and paths that will bear weight — an uncompacted sub-base settles unevenly. Compaction can reduce the finished depth by 10–20%, which this calculator does not account for.
What's the difference between gravel and crushed stone for a base layer?
Crushed, angular stone locks together and compacts more stably than rounded gravel, which is why it's the more common choice under driveways and patios. Rounded pea gravel is more often used as a decorative top layer.
Last updated 2026-07-01. Formulas are planning methods — confirm with a supplier before you order.