How it works
Volume is length × width × depth. The only wrinkle is that depth is usually quoted in a smaller unit than the plan dimensions — inches against feet, or millimetres against metres — so it's converted to match before multiplying, then the raw volume is converted again into the unit suppliers actually sell by.
This calculator gives volume only — for material-specific figures like bag counts or weight, see the Gravel Calculator or Mulch Calculator, which build the same volume calculation forward into what you'd actually order.
Worked example
A 10 ft × 10 ft area, filled 6 inches deep.
- Convert depth to feet: 6 ÷ 12 = 0.5 ft.
- Multiply out: 10 × 10 × 0.5 = 50 ft³.
- Convert to cubic yards: 50 ÷ 27 = 1.85 yd³.
You'd need about 1.85 cubic yards (50 ft³).
Common questions
Why cubic yards instead of cubic feet?
Bulk materials like soil, mulch and aggregate are almost always priced and delivered by the cubic yard (or cubic metre outside the US) — cubic feet is the unit the arithmetic naturally produces, but not the one you'd order in, so both are shown.
Should I order exactly this amount?
Most suppliers and contractors round up and add 5–10% for an uneven subgrade or settling, especially for loose fill. This calculator gives the raw geometric volume; build in your own margin on top for material that compacts or settles after placement.
Does this account for compaction?
No — this is the volume of the finished, in-place space you want to fill. Loose material typically takes up more volume before compaction than after, so you may need more delivered material than this raw figure to account for settling.