Sand Volume Calculator

Sand volume calculator for bedding layers and fill depth

This sand volume calculator estimates how much sand you need to cover a rectangular area at a specific depth. The common use case is planning a sand bedding layer under paving, a thin leveling layer in a landscaping project, or a shallow fill layer where you already know the length and width of the space. The primary output is volume in cubic meters (m³), because that is how sand is commonly priced and delivered in many regions. If you add the optional settings, it also estimates weight and a rough bag count.

To use it, measure the length and width of the area in meters, then enter the depth in millimeters. Depth is in millimeters because most sand layers are specified as a thin thickness (for example 30 mm to 70 mm) rather than fractions of a meter. Click calculate and the tool will show the area, the depth converted to meters, the base volume, and a practical “recommended order volume” after applying an allowance. If you leave the advanced inputs blank, the calculator still works and uses sensible defaults.

The results are meant for ordering, not laboratory precision. Sand behaves differently depending on moisture, compaction, and how it is handled. That is why the calculator supports a waste or compaction allowance and a density value. In real projects, you usually need more sand than the pure geometric volume suggests because the sand settles, some is lost during spreading, and uneven surfaces increase the true required depth in places. The allowance helps you move from “math volume” to “order volume” without needing perfect information.

Assumptions and how to use this calculator

• The area is treated as a simple rectangle, so the calculation assumes a consistent length and width across the whole space.
• Depth is assumed to be reasonably uniform after spreading and leveling; if the base is uneven, use a higher allowance percentage.
• If you leave waste/compaction blank, the calculator uses a default allowance of 10% to cover settling and handling losses.
• If you leave density blank, the calculator uses 1600 kg per m³ as a practical dry-sand estimate; wet sand can be heavier.
• Bag estimates are a convenience only and assume a constant bag size and consistent density; use them for planning, not exact purchasing.

Common questions

What is the formula this sand volume calculator uses?

The base calculation is volume = length × width × depth, with depth converted from millimeters to meters. If you add an allowance, the calculator multiplies the base volume by (1 + allowance% ÷ 100). This keeps the math simple while still producing a realistic ordering figure.

What depth should I use for a sand bedding layer under paving?

This depends on the paving system and the base preparation. Many projects use a thin bedding layer that is compacted and leveled, but you should use the depth specified by your installer, product guidelines, or local practice. If you are unsure, enter the depth you plan to spread, then rely on the allowance to reduce the risk of under-ordering.

Why does the calculator include a waste or compaction allowance?

Sand is rarely used in perfectly controlled conditions. It settles when compacted, some is lost during transport and spreading, and uneven sub-bases create thicker spots. The allowance converts a geometric volume into a more practical “order volume.” If your base is rough or you expect heavy compaction, increase the allowance.

How do I improve accuracy if I do not know sand density?

If weight matters, use your supplier’s density or product data if available. Density varies with moisture content and grain type, so default values can be off. If you cannot get a density figure, treat the weight and bag counts as rough guidance and focus on the cubic meter volume for ordering.

Does this calculator work for non-rectangular areas?

No. This page is intentionally locked to rectangular areas because it matches the most common search intent and keeps inputs minimal. For irregular spaces, break the area into rectangles, calculate each one, then add the volumes together before ordering.