Which sand you need: concrete, mason, fill, and play sand
Sand is not one product. The yard stocks several sands, each screened and washed for a different job, and the wrong one fails even when the tonnage is right. Pick the sand by the task first, then size the order with this calculator. The amount comes from your area and depth, but the grade comes from what the sand has to do.
Concrete sand, also called sharp sand or ASTM C33 sand, is a coarse, angular sand screened for mixing concrete. Its grains are gritty and run across a range of sizes, which is what lets a concrete or mortar mix grip. The same traits make it the common choice for a paver bedding course and for filling the joints between pavers, where it locks in place instead of washing out.
Mason sand is a finer, more even sand, washed and screened smooth for mortar and plaster. Masons use it where a coarse grit would show in a thin joint. It also serves as a clean play sand and a soft fill. Because it is finer than concrete sand, it packs tight and holds water longer, so it makes a poor bedding sand under pavers.
Fill sand is the cheap, unwashed sand you buy in bulk to raise grade, backfill a trench, or build up a low area. It carries more silt and fine material than a washed sand, so it is not for a finished surface or a concrete mix. Play sand sits at the other end: a fine sand that is washed, screened, and often sifted again so it is clean and safe for a sandbox.
Ask your supplier for the sand by name, not just sand, because a yard may stock four or five grades at different prices. Confirm whether it is washed or unwashed, coarse or fine, before you load. The calculator sizes the volume the same way for any grade, so once you know the right sand, the area and depth give you the tons to order.