Gravel Calculator
Find out how much gravel your driveway, path, or base layer needs: volume in cubic metres and yards, weight in tonnes for ordering from a landscape supplier, and how many bags that works out to for small jobs.
Your results
Worked example
A parking pad is 5 m by 5 m, so the area is 25 m². With a depth of 5 cm and typical crushed gravel density:
- Volume: 25 m² × 0.05 m = 1.25 m³
- In cubic yards: 1.25 × 1.30795 = 1.63 yd³
- Weight: 1.25 m³ × 1.6 tonnes per m³ = 2.00 tonnes
- In bags: 2,000 kg ÷ 30 kg per bag = 66.7, so 67 bags
At the loose, dry density of 1.4, the same pad would weigh 1.75 tonnes. At the damp or compacted density of 1.7, it would weigh 2.13 tonnes. That spread is why suppliers quote gravel by the tonne and why a small over-order is common.
How this calculator works
Gravel is priced by weight at most Canadian landscape yards, so this calculator converts volume to weight:
The density assumption is stated openly because it is the biggest source of error in any gravel estimate. Dry, loose pea gravel and crusher run are often estimated near 1.4 to 1.5 tonnes per cubic metre. Standard crushed gravel is commonly estimated at about 1.6 tonnes per cubic metre, which is the default here. Damp or compacted material runs closer to 1.7. Bag counts use a standard 30 kg bag, the common size at Canadian building centres, and always round up. Depths entered here are finished depths; loose gravel compacts, so a base layer should be ordered with a little extra.
Common questions
How deep should gravel be on a driveway?
A common build is a compacted base of 10 to 15 cm of crusher run, topped with about 5 cm of decorative or driveway gravel. For a simple top-up of an existing drive, 5 cm is typical.
Why do suppliers sell gravel by the tonne instead of the yard?
Weight is exact, volume is not: a loose cubic yard and a compacted cubic yard contain different amounts of stone. This calculator shows both, and the worked example shows how much the density choice moves the answer.
How accurate is the 1.6 tonnes per cubic metre figure?
It is the widely used planning estimate for crushed stone and gravel. Real material varies with rock type, moisture, and how it is loaded. For a large order, ask your yard for their conversion for the specific product you are buying.
Should I order extra gravel?
Most people order 5 to 10 percent extra to cover compaction and low spots. Running short mid-job usually costs more in a second delivery fee than the extra material costs.
Estimates only. Results are provided for planning purposes and are based on the density and bag-size assumptions shown on this page. Actual weight varies with material type, moisture, and compaction. Confirm the conversion and price with your supplier before ordering. Mississippi Maple accepts no liability for purchase decisions made using this calculator.