Topsoil Calculator — cubic yards and tons

How it works

Topsoil for a garden bed, lawn or raised bed is worked out by volume, then converted to weight if your supplier sells by the ton:

cubic yards = (length × width × depth) ÷ 27

with dimensions in feet (depth is entered in inches and converted, ÷12). Dividing by 27 gives cubic yards, since one cubic yard is 27 cubic feet.

For weight, multiply the cubic yards by the density:

tons = cubic yards × density

Screened topsoil runs around 1.1 tons per cubic yard — lighter than gravel or sand — but wet or heavy soil weighs more, so density is an input. Order a little extra, since soil settles after spreading and watering.

Worked example

A 20 × 10 ft garden at 4 inches deep is 20 × 10 × 0.333 = 66.7 cubic feet = 2.47 cubic yards, about 2.7 tons at 1.1 t/yd³. A 40 × 20 ft lawn topped with just 2 inches comes to about 4.94 cubic yards, and an 8 × 4 ft raised bed filled 10 inches deep needs about 0.99 cubic yards.

Frequently asked questions

How much topsoil do I need?

Multiply length × width × depth in feet and divide by 27 for cubic yards. If the depth is in inches, divide it by 12 first. For weight, multiply the cubic yards by about 1.1 tons per cubic yard for screened topsoil.

How many tons is a cubic yard of topsoil?

Around 1.1 tons per cubic yard for dry, screened topsoil — lighter than gravel (about 1.4) or sand (about 1.35). Wet, dense or unscreened soil weighs more. Enter your supplier's density for an accurate tonnage.

How deep should topsoil be?

For a new lawn, 4–6 inches of quality topsoil gives roots room to establish; for top- dressing an existing lawn, ¼–½ inch. Garden beds often want 6–12 inches, and raised beds are filled to their depth. Deeper is better for root crops.

Should I order extra topsoil?

Yes — add about 5–10%. Topsoil settles and compacts after it is spread and watered, so a fresh layer loses some depth. It is easier to have a little left over for top-dressing than to reorder a small amount.

Is topsoil sold by the yard or the bag?

Both. Bulk topsoil is sold by the cubic yard (cheaper for large areas and delivered by truck); bagged topsoil comes in cubic-foot bags for small jobs. To convert, remember one cubic yard is 27 cubic feet, so about 13–14 of the common 2 ft³ bags.

What is the difference from the gravel or sand calculators?

The volume math is identical — area times depth. The materials differ mainly in **density**: topsoil is lightest (~1.1 t/yd³), sand is heavier (~1.35), and gravel heavier still (~1.4). Each calculator defaults to its material's typical density, which you can adjust.