How to use the sand calculator
- Enter the area: length and width for a sandbox or pad, diameter for a round above-ground pool, or a known total.
- Enter the depth of sand you want.
- Choose dry, damp or wet sand. Bulk sand from an outdoor pile is often damp and weighs more per yard.
- Pick a bag size if buying bagged play sand, and add a price to compare bulk vs. bags.
The sand formula
Cubic feet = area (sq ft) × depth (in) ÷ 12
Cubic yards = cubic feet ÷ 27 · Tons = cubic feet × density ÷ 2,000
The Engineering ToolBox lists dry sand at 1,602 kg/m³ (100 lb/ft³) and wet sand at 1,922 kg/m³ (120 lb/ft³). That means a cubic yard weighs about 2,700 lb dry and up to 3,240 lb wet. A 50 lb bag of dry sand is about 0.5 cu ft, so it takes 54 bags to make a cubic yard.
How deep should sand be?
- Sandbox: 6–12 inches. Deeper sand lets kids dig without hitting the bottom.
- Above-ground pool base: about 2 inches of masonry sand over level, compacted soil, unless the manufacturer specifies otherwise.
- Paver bedding: 1 inch of coarse concrete sand, screeded flat; see the paver sand calculator.
- Lawn leveling / top-dressing: 1/4 to 1/2 inch at a time, usually a sand-soil mix.
- Under a hot tub or shed pad: 1–2 inches as a leveling layer over a compacted gravel base.
Worked example: sandbox
A 6 × 6 ft sandbox filled 8 inches deep, with 5% extra:
- Area: 6 × 6 = 36 sq ft
- Volume: 36 × 8 ÷ 12 = 24 cu ft; with 5% = 25.2 cu ft
- Cubic yards: 25.2 ÷ 27 = 0.93 yd³
- Weight dry: 2,520 lb = 1.26 tons
- Bags: 2,520 ÷ 50 = 51 bags of 50 lb
Worked example: round above-ground pool
For a 24 ft round pool, choose Circle and enter a 24 ft diameter (many installers add 1–2 ft so the sand extends past the wall). At 2 inches deep: area 452 sq ft × 2 ÷ 12 = 75.4 cu ft = 2.8 yd³, about 3.8 tons of dry sand.
Types of sand
- Play sand: washed, screened and fine; sold in bags for sandboxes.
- Masonry sand: fine and smooth; used for mortar, pool bases and volleyball courts.
- Concrete sand: coarser, with angular grains; best under pavers and in concrete.
- Fill sand: unwashed and cheaper; for filling holes and building up grade.
Tips
- Bulk sand is almost always cheaper than bags above about half a yard.
- Cover sandboxes when not in use to keep out rain, leaves and animals.
- Ask whether the supplier's price is for dry or damp sand if you are buying by the ton.
Frequently asked questions
How much does a cubic yard of sand weigh?
About 2,700 lb (1.35 tons) dry and up to about 3,200 lb (1.6 tons) wet.
How many bags of sand do I need for a sandbox?
A 6 × 6 ft sandbox at 8 inches deep holds 24 cu ft, about 48 bags of 50 lb play sand before any extra.
How much area does a ton of sand cover?
At 100 lb/ft³, a ton is 20 cubic feet, enough for 240 sq ft at 1 inch, 120 sq ft at 2 inches or 80 sq ft at 3 inches.
How many 50 lb bags of sand are in a yard?
About 54 bags, because a cubic yard of dry sand weighs roughly 2,700 lb.
How much sand do I need under an above-ground pool?
Plan about 2 inches. A 24 ft round pool needs roughly 2.8 cubic yards, or about 3.8 tons, of masonry sand.