Sand Calculator
Figure out how much sand a sandbox, paver base, or bedding layer needs: volume in cubic metres and yards, weight in tonnes for ordering from a landscape yard, and how many 25 kg bags that works out to if you buy it bagged.
Your results
Worked example
A sandbox is 3 m by 3 m and gets filled 15 cm deep:
- Area: 3 m × 3 m = 9 m²
- Volume: 9 m² × 0.15 m = 1.35 m³
- In cubic yards: 1.35 × 1.30795 = 1.77 yd³
- Weight: 1.35 m³ × 1.6 tonnes per m³ = 2.16 tonnes
- Bags: 2,160 kg ÷ 25 kg per bag = 86.4, rounded up to 87 bags
That is a small bulk load for most landscape yards, or 87 bags if bought bagged, which is why bulk delivery usually wins on any sandbox-sized job.
How this calculator works
Dry sand is commonly estimated at about 1.6 tonnes per cubic metre, the figure used here and stated openly because density is the largest source of error in any sand estimate. Wet sand weighs more per cubic metre, up to about 1.9 tonnes, so a load ordered after heavy rain can weigh noticeably more than the same volume in dry weather. Yards sell sand by the tonne or by the cubic yard; this calculator shows both measures. The bag count uses one standard size, a 25 kg bag of dry sand, at the same 1.6 tonnes per cubic metre density.
Common questions
How deep should sand be in a sandbox?
About 15 cm gives kids room to dig without reaching the base fabric quickly. Deeper fills settle and need topping up less often, but add weight and cost.
Why does wet sand weigh more?
Water fills the air gaps between sand grains. The volume barely changes, but the mass can rise by 15 to 20 percent. If your yard sells by the tonne, the same pile simply costs more when wet.
Estimates only. Results are provided for planning purposes and use the dry sand density of 1.6 tonnes per cubic metre stated on this page. Bag counts assume 25 kg bags at that same density. Actual weight varies with moisture and sand type. Confirm the conversion and price with your supplier before ordering. Mississippi Maple accepts no liability for purchase decisions made using this calculator.