How much topsoil do you need?
Like mulch and gravel, topsoil is sold by volume: in bags measured in cubic feet, or in bulk by the cubic yard. The amount you need is the area you are covering multiplied by the depth. Because loose soil settles once it is watered and walked on, it is sensible to order a little extra.
How the calculator works
- It works out the area in square feet from your shape and measurements.
- It multiplies by the depth (inches ÷ 12) to get cubic feet and adds your settling allowance.
- It divides by 27 for cubic yards, multiplies by the weight per yard for tons, and divides by the bag size for the number of bags.
The formula
Topsoil weight varies a lot with moisture and composition. Dry, screened topsoil is lighter than wet soil with a lot of clay. The default of 1.1 tons per cubic yard is only a starting point, so use your supplier's figure if they sell by weight.
Worked example
You want to spread 2 inches of topsoil over a 20 × 30 ft area before reseeding. The area is 600 sq ft, and 600 × 2 ÷ 12 = 100 cubic feet. Adding 10% for settling gives 110 cubic feet, or about 4.07 cubic yards.
That is roughly 4.5 tons at 1.1 tons per yard, or 147 bags of 0.75 cubic feet. At that size, bulk delivery is almost always cheaper than bags.
How deep should topsoil be?
| Project | Typical depth |
|---|---|
| Top-dressing an existing lawn | ¼–½ in per application |
| Filling low spots before seeding | 1–2 in |
| New lawn from seed or sod | 4–6 in |
| New flower or vegetable bed | 6–12 in |
| Raised bed | The full depth of the bed |
When top-dressing an existing lawn, apply thin layers so the grass can grow through. Thick layers can smother it.
Tips before you order
- Bulk or bags? One cubic yard is 36 bags of 0.75 cubic feet. For anything over about a cubic yard, bulk delivery is usually cheaper, though delivery fees and minimum orders apply.
- Ask what you are getting. "Topsoil" can mean very different things. Screened topsoil has stones and roots removed; garden blends mix in compost. For vegetable beds a blend is usually better.
- Plan the drop spot. A delivery truck will usually dump the load in one pile. Have a tarp down and a wheelbarrow ready.
- For raised beds, many gardeners mix topsoil with compost for better drainage and nutrients.
Frequently asked questions
How many bags of topsoil are in a yard?
A cubic yard is 27 cubic feet, so it equals 36 bags of 0.75 cubic feet, 27 bags of 1 cubic foot or 13.5 bags of 2 cubic feet.
How much does a yard of topsoil weigh?
Very roughly 1 to 1.4 tons, depending on moisture and composition. Wet, clay-heavy soil is at the high end. Your supplier can give the figure for their product.
How much area does a yard of topsoil cover?
One cubic yard covers about 324 square feet at 1 inch deep, 162 square feet at 2 inches and 81 square feet at 4 inches.
Should I order extra topsoil?
Yes. Loose soil settles once it is compacted and watered, so adding about 10–20% is common.
Is topsoil the same as garden soil?
Not always. Topsoil is the upper layer of natural soil; garden soil or bed mixes usually add compost and other organic matter for planting.
Last reviewed November 2026. Spotted an error? Tell us.