Sand looks simple and weighs a fortune — one cubic yard is well over a ton — so estimating by eye usually ends in either a second trip or a heavy surprise. This calculator turns your area and depth into cubic yards, tons and 50 lb bags, using the right density for the sand you are buying.
The formula
Moisture is the swing factor: the same yard of sand weighs roughly 1.35 tons bone dry and up to 1.55 tons after rain, because water fills the gaps between grains. If your supplier sells by weight and the pile is wet, you are partly buying water — another reason the “extra allowance” here defaults to a modest 5%.
Which sand for which job?
Paver and bedding sand is coarse and angular so it locks together under pavers — a 1 inch bedding layer over compacted gravel is standard. Mason/concrete sand is washed and graded for mixing mortar and concrete. Play sand is washed, rounded and screened for sandboxes. Jointing sand is very fine and dry so it sweeps deep into paver joints. They are not interchangeable: play sand under pavers stays soft, and coarse bedding sand makes miserable mortar.
Worked example
A paver base area of 10 ft × 10 ft with a 2 inch sand layer: volume = 100 × (2/12) = 16.67 ft³ = 0.62 yd³. Dry sand at 1.35 t/yd³ weighs 0.83 tons (1,667 lb), so with a 5% allowance you order about 0.88 tons — or 35 × 50 lb bags.
How to use this tool
- Measure the area and enter its length and width.
- Enter the depth of sand — 1 inch for paver bedding, more for sandboxes and levelling.
- Choose the sand type; density is what turns volume into tons.
- Add a small extra allowance for spillage and uneven subgrade.
- Compare the tonnage with the 50 lb bag count and pick the cheaper route — usually bulk over about half a ton.
Sand under pavers: the two-layer rule
A lasting paver job is 4–6 inches of compacted gravel, then exactly 1 inch of coarse bedding sand screeded level — never use the sand layer to fix a bumpy base, and never lay it thicker than about 1½ inches, or the pavers will rock and rut. Fine jointing sand is swept in afterwards to lock the surface.