Topsoil Calculator
Work out how much topsoil you need for a lawn, garden or raised bed, in cubic yards, tons and cost. The calculator starts with a typical new-lawn depth and soil weight.
Why topsoil is different
Topsoil is the loose, nutrient-rich layer plants root in. It is usually bought by the cubic yard for lawns and garden beds, and by the bag for pots and small beds. It is lighter than gravel or sand and its weight changes more with moisture, so volume is the more reliable way to order it.
The volume calculation is area times depth, as in the gravel calculator. For beds with mulch on top, the mulch calculator works out the cover.
How deep should topsoil be?
Gardening guides commonly suggest these depths. They are common starting points, and your existing soil and the plants you are growing change them.
| Use | Common depth |
|---|---|
| New lawn | about 4 to 6 inches |
| Raised bed | about 6 to 12 inches, deeper for root crops |
How far does a cubic yard go?
A cubic yard is 27 cubic feet. Spread at different depths it covers:
| Depth | Area per cubic yard |
|---|---|
| 2 inches | 162 sq ft |
| 3 inches | 108 sq ft |
| 4 inches | 81 sq ft |
| 6 inches | 54 sq ft |
Worked example
A lawn area 40 ft by 25 ft, covered with 4 inches of topsoil, with 10 percent extra for settling and 1.1 tons per cubic yard.
- Area: 40 × 25 = 1,000 sq ft
- Volume: 1,000 × (4 ÷ 12) = 333 cu ft, which is 12.35 cu yd
- With 10 percent extra: 13.58 cu yd
- Weight: 13.58 × 1.1 = 14.9 tons
A load that size is usually delivered in bulk, so order by the cubic yard where you can.
Questions
How much does a cubic yard of topsoil weigh?
Often around 2,200 pounds, or about 1.1 tons, but it varies a lot with moisture and how much organic matter or sand it contains. Reported figures range from the 70s to the 100s of pounds per cubic foot. The calculator starts at 1.1 tons per cubic yard. Use your supplier's figure if they give one.
How deep should topsoil be for a new lawn?
Common guidance is about 4 to 6 inches of topsoil for a new lawn. If you already have decent soil, you may need less. Ask your supplier or a local garden center what suits your site.
How much topsoil do raised beds need?
Raised beds are usually filled much deeper than lawns. Guides often suggest around 6 to 12 inches, and deeper for root crops. Fill the whole bed, so measure its length, width and the full depth.
Should I allow for settling?
Yes. Loose topsoil settles after it is spread and watered, so the finished layer ends up thinner than the loose one. The extra allowance field covers that, and 10 percent is a common starting figure.
Do suppliers sell topsoil by the yard or by the ton?
Both are common. Bulk topsoil is usually sold by the cubic yard, which avoids the problem of weight changing with moisture. Bagged topsoil for small jobs is sold by volume in cubic feet. Check how your supplier measures it before you compare prices.