How it works
The calculator multiplies the area by the depth, adds any extra you enter, and divides by the bag volume. If you give a density, it also multiplies the volume by it to get the weight.
Area = Length × Width
Volume = Area × Depth × (1 + Extra ÷ 100)
Bags = ⌈ Volume ÷ Bag volume ⌉
Weight = Volume × Weight per volume
Cubic yards = Cubic feet ÷ 27
⌈ ⌉ means rounding up to the next whole bag. Units are converted internally, so you can enter the area in feet, the depth in inches and the density in tons per cubic yard or pounds per cubic foot.
Common uses
Sand is bought for very different jobs: filling a sandbox, a bedding layer under pavers or flagstones, leveling under a pool or a shed base, or as fill around pipes. The arithmetic is the same for all of them – area × depth – but the kind of sand is not. SAKRETE’s play sand sheet, for example, says “for use only as play sand”, and CMHA asks for concrete sand (ASTM C33) under pavers rather than mason sand or stone dust. Pick the product the job calls for, then use its bag yield here.
Bags: read the yield, not just the weight
Packaged sand is labelled by weight – 50 lb, 60 lb or 25 kg – but you fill a volume. Manufacturers publish the volume a bag fills: SAKRETE’s play sand sheet says to divide the volume to fill by 0.5 cubic feet per 50 lb bag, and SAKRETE Canada gives about 0.0175 m³ (17.5 L) loose for a 25 kg bag of multi-purpose sand. Those are the example values here. A different product, or the same weight of a different sand, can fill a different volume, so replace them with your product’s figure.
Bulk sand and weight
For larger jobs sand is sold loose by the cubic yard, the cubic meter or the ton. To convert between volume and weight you need the supplier’s density for that exact sand, because grading and moisture change it. Enter it under More options and the calculator shows the weight; without it you still get the volume to order.
Compacted vs loose
Sand settles and compacts. SAKRETE Canada’s figures for a 25 kg bag – about 0.0175 m³ loose and 0.015 m³ compacted – show the difference: the compacted volume is roughly a seventh smaller. If the sand will be tamped or wetted down, enter an extra allowance so you order enough loose sand.
Worked example
Inputs
- Measure by
- Length × width
- Area length
- 6 ft
- Area width
- 6 ft
- Sand depth
- 4 in
- Bag volume
- 0.5 cu ft
- Extra
- 0 %
Result
- Sand volume
- 12 cu ft (0.444 cu yd)
- Bags
- 24
Common mistakes
- Entering the depth in feet instead of inches. Four inches is a third of a foot; a wrong unit multiplies the order by twelve.
- Treating a bag’s weight as its volume. A 50 lb bag does not hold a fixed number of cubic feet for every sand – use the yield on the bag or data sheet.
- Using the compacted depth for loose sand you will tamp. Sand compacts, so more loose sand goes in than the finished layer suggests.
- Buying the wrong kind of sand. Play sand, concrete sand and mason sand are graded differently; use what the project or the product instructions call for.
- Confusing US short tons with metric tonnes. A short ton is 2,000 lb, a metric tonne is 1,000 kg.
Assumptions and limits
- The area is a rectangle, or you have entered its total area, and the depth is the same everywhere.
- Bags are the volume divided by the bag volume you enter, rounded up to whole bags.
- Weight is the volume × the density you enter. No density is assumed; without one, only the volume and bags are shown.
- Compaction and settling are covered only by the extra allowance you enter.
Frequently asked questions
How many bags of sand do I need for a sandbox?
Multiply length × width × depth to get cubic feet, then divide by the volume of one bag. SAKRETE’s play sand sheet uses exactly this method with 0.5 cu ft per 50 lb bag – its example is a 4 × 4 ft box filled 4 in deep, which needs 11 bags. The calculator does the same with your own sizes.
How much does a cubic yard of sand weigh?
It depends on the sand and its moisture, so ask your supplier for the figure for the product you buy and enter it under Weight per volume. The calculator does not assume one.
How deep should sand be under pavers?
The Concrete Masonry & Hardscapes Association (CMHA, formerly ICPI) says bedding sand should be screeded to an uncompacted nominal 1 in (25 mm). For the whole base under pavers – crushed stone plus bedding sand – use the paver base calculator.
Can I use this for other loose materials?
For the volume, yes – any material spread in an even layer works the same way. Enter the bag volume and density for that material, or use the gravel, topsoil or mulch calculator.
Sources
- Natural Play Sand – product data sheet (REV 3-10) — SAKRETE. Bag count: "Divide the cubic volume of the area to be filled by 0.5 cubic feet"; a 50 lb bag yields "6 sq. ft. x 1 inch" (US bag default 0.5 cu ft).
- SAKRETE Multi-Purpose Sand – product data sheet — King Packaged Materials Company (Sika Canada). "25 KG (55 lb) yields approximately" 0.0175 m³ not compacted and 0.015 m³ compacted (metric bag default 17.5 L).
- PAV-TEC-002-22 – Construction of Interlocking Concrete Pavements — Concrete Masonry & Hardscapes Association (formerly ICPI). "Sidewalks, patios and pedestrian areas should have a minimum base thickness (after compaction) of 4 in. (100 mm) over well-drained soils"; "Bedding sand should be spread and screeded to an uncompacted nominal 1 in. (25 mm) thickness."
- NIST Handbook 44, Appendix C – General Tables of Units of Measurement — National Institute of Standards and Technology. Exact unit definitions: 1 in = 2.54 cm, 1 yd³ = 27 ft³, 1 US gal = 231 in³, 1 lb = 0.45359237 kg.
Method reviewed November 4, 2026