Topsoil Calculator
Estimate topsoil for a new lawn, raised bed, or grading job — in cubic yards, tons, and bags.
How to calculate topsoil
Topsoil is sold by volume or weight. Measure the area in feet, convert the depth from inches to feet, then divide by 27 for cubic yards. Multiply cubic yards by about 1.2 to estimate tons.
Length × width × (depth ÷ 12) = cubic feet. Cubic feet ÷ 27 = cubic yards. Cubic yards × 1.2 = tons (planning estimate).
Example: 20 × 10 ft at 6 inches deep is 100 cubic feet, or 3.7 cubic yards. With 10% waste, that is about 4.07 cubic yards, 4.9 tons, or 147 bags of 0.75 cu ft topsoil.
Topsoil coverage chart
| Depth | 1 cubic yard covers | 40 lb bags per 100 sq ft |
|---|---|---|
| 1 in | 324 sq ft | 12 |
| 2 in | 162 sq ft | 23 |
| 3 in | 108 sq ft | 34 |
| 6 in | 54 sq ft | 67 |
Based on a 40 lb bag holding about 0.75 cubic feet. Check the bag label; some brands sell 1 or 1.5 cu ft bags.
How deep should topsoil be?
- New lawn: 4–6 inches, mixed into the existing soil.
- Garden beds: 6–8 inches for vegetables and deep-rooted plants.
- Raised beds: fill the bed, but mix topsoil with compost rather than using straight subsoil.
- Overseeding and leveling: 1/4–1/2 inch; too much smothers existing grass.
- Grading and fill: 1–2 inches per pass, compacted in lifts.
Bulk vs. bags
| Bulk topsoil | 40 lb bags | |
|---|---|---|
| Typical price | $25–$40 per cubic yard | $3.00–$4.50 per bag |
| 100 sq ft at 6 in | About $50–$80 | About $200–$300 |
| Best for | Lawns, beds, grading | Small patches, raised beds, touch-ups |
| Watch for | Delivery, minimum loads, quality | Bag yield, moisture, compaction |
Bulk is almost always cheaper for a lawn or a full bed. Bags make sense for a few square feet, a single raised bed, or a site a truck cannot reach.
Screened vs. unscreened topsoil
Screened topsoil is sifted and easier to spread; it costs more but has fewer rocks and clods. Unscreened topsoil is cheaper for fill and grading but may contain debris. For a lawn or garden bed, pay for screened soil and ask for the source.
Before you order
- Measure each area separately and add 10% for settling.
- Ask whether the price is per yard or per ton; the conversion is about 1.2 tons per yard.
- Confirm delivery access and whether the driver can dump where you need it.
- For beds, plan to mix in compost rather than filling with straight topsoil.
- Do not cover existing grass by more than half an inch unless you are renovating.
Frequently asked questions
How many bags of topsoil are in a cubic yard?
A 40 lb bag of topsoil holds about 0.75 cubic feet. Since a cubic yard is 27 cubic feet, you need about 36 bags per yard. Bag yields vary, so check the label before buying a pallet.
How much topsoil do I need for 100 square feet?
At 6 inches deep, 100 square feet needs 50 cubic feet, or about 1.85 cubic yards. That is roughly 2.2 tons and 67 bags of 0.75 cu ft topsoil before waste.
How many tons are in a yard of topsoil?
Topsoil weighs about 1.1 to 1.3 tons per cubic yard, depending on moisture and organic content. The calculator uses 1.2 tons per yard for planning.
How deep should topsoil be for a new lawn?
Spread 4 to 6 inches of topsoil for a new lawn, then mix it into the existing soil. For garden beds, 6 to 8 inches is better. For overseeding or leveling, a quarter to half inch is enough.
Is topsoil the same as compost?
No. Topsoil is mineral soil used for fill, grading, and building a root zone. Compost is decomposed organic matter used to improve fertility and structure. For beds, a mix of topsoil and compost usually works best.