Soil Calculator

For a new rectangular bed, measure its inside length, inside width, and the depth that will actually contain soil. For topdressing a lawn, use the lawn area and the thickness of the new layer. For an existing bed, measure the remaining space rather than its full wall height.

An 8 ft by 4 ft raised bed filled 12 inches deep holds 32 cubic feet, or about 1.185 cubic yards. If it has only 8 inches left to fill, the remaining volume is 8 × 4 × 8 ÷ 12 = about 21.333 cubic feet, or 0.790 cubic yards. With bags labeled 2 ft³, divide 21.333 by 2 and round up to 11 whole bags before any extra allowance. Measure the unfilled depth instead of ordering for the full wall height.

Add each bed as a separate area when dimensions or depths differ. Round and triangular beds can be entered using their matching shapes. Known area accepts square feet, square yards, or square meters plus depth.

Topsoil, compost, raised bed blends, and general fill dirt are different materials. The calculator measures space; it does not decide which material suits the plants or supply a universal soil blend. Follow a suitable growing plan or supplier specification.

If a recipe calls for parts by volume, divide the total among those parts. For example, an explicitly chosen two to one blend would allocate two thirds and one third of the starting ingredient volumes. Mixing and settling can affect the finished volume.

Enter the bag’s labeled volume under Ordering options. The bag field uses cubic feet. For soil labeled in US dry quarts, use the gallon and quart converter to obtain cubic feet first; liquid and dry quarts are different units.

The 32 ft³ raised bed example needs 16 bags of 2 ft³ each. A different bag yield changes the count. Buying one cubic yard in 2 ft³ bags requires 14 whole bags because 27 ÷ 2 = 13.5.

A delivered cubic yard is a volume, not a fixed weight. Moisture and compaction can alter bulk density. Use a supplier density for the same moisture condition and loose or compacted state as your volume if you need pounds or tons. Convert the volume state first when these differ. Soil can settle after placement; use a project specific allowance rather than treating one percentage as correct for every bed.

Enter a quoted volume price to estimate material cost. Soil quality, screening, blending, delivery, and minimum orders can affect what you pay. For a known delivery quantity, the yard of dirt guide helps compare its coverage and a supplier quote.