Landscaping
Topsoil Calculator
Use this topsoil calculator to work out how much soil you need for a new lawn, garden beds or raised beds. It turns your measurements and depth into cubic yards and tons, adds an allowance for settling, and shows how many bags that would be, with an optional cost for bulk or bagged soil.
Result
Enter your measurements and press Calculate. What to buy, the working and the cost will appear here.
How to use the topsoil calculator
- Measure each area: a rectangle for beds and lawns, a circle for round beds, or a known area in square feet.
- Set the depth of soil for each area. Raised beds are often 8–12 in deep; a new lawn needs 4–6 in.
- Choose the soil type. Topsoil, garden blend, compost and fill dirt have different weights.
- Keep the settling allowance at 15% unless your supplier says otherwise; loose soil sinks once watered.
- Add a price per cubic yard, per ton or per bag, then press Calculate.
How much topsoil do I need?
cubic yards = length (ft) × width (ft) × depth (in) ÷ 324
tons = cubic yards × weight per cubic yard
A 20 ft × 10 ft area at 4 inches deep is 200 × 4 ÷ 324 = 2.47 cubic yards. At about 1.1 tons per yard that is 2.7 tons, before the settling allowance.
Worked example: filling two raised beds
Two raised beds are 8 ft × 4 ft and 12 inches deep. They will be filled with a topsoil and compost garden blend, with 15% extra for settling, at $45 per cubic yard delivered:
- Area 1: 8 ft × 4 ft = 32 ft²; × 12 in (1 ft) = 32 ft³
- Area 2: 8 ft × 4 ft = 32 ft²; × 12 in (1 ft) = 32 ft³
- With allowance: 2.37 yd³ × 1.15 = 2.726 yd³
- Weight: 2.726 yd³ × 0.9 tons/yd³ = 2.45 tons
- Bags: 73.6 ft³ ÷ 0.75 ft³ per bag = 99 bags
Order 2.73 yd³ (about 2.45 tons). Rounded up to half-yard steps that is 3 yd³, roughly $135.00. The same soil in bags would be 99 bags of 0.75 ft³. Open this example in the calculator.
Topsoil coverage chart
| Depth | One cubic yard covers | One ton covers (screened topsoil) |
|---|---|---|
| 1 in | 324 ft² | 295 ft² |
| 2 in | 162 ft² | 147 ft² |
| 4 in | 81 ft² | 74 ft² |
| 6 in | 54 ft² | 49 ft² |
| 12 in | 27 ft² | 25 ft² |
How much topsoil depth do you need?
- Top-dressing a lawn: ¼–½ in of screened topsoil or compost, raked into the grass.
- New lawn from seed or sod: 4–6 in of topsoil over loosened subsoil.
- Flower and shrub beds: 6–8 in of good soil.
- Raised vegetable beds: 8–12 in or more; many gardeners fill the bottom with cheaper soil or fill and top with a rich garden blend.
- Raising grade: fill dirt for the bulk, with 4 in or more of topsoil on top where you want plants to grow.
Soil types and weights
| Soil | Per cubic yard | Allowance | Notes |
|---|---|---|---|
| Screened topsoil | 1.1 tons2,200 lb | 15% | Loose screened soil for lawns and beds; settles 10–20% after spreading and watering. |
| Garden soil (topsoil and compost blend) | 0.9 tons1,800 lb | 15% | Richer mix for vegetable and flower beds. |
| Compost | 0.6 tons1,200 lb | 10% | Light organic matter for top-dressing and mixing into beds. |
| Fill dirt | 1.2 tons2,400 lb | 20% | Unscreened subsoil for raising grade or filling holes; compacts noticeably. |
Wet soil can weigh noticeably more than these figures. If your supplier quotes a weight per yard, enter it in the calculator.
Buying topsoil
- Bulk is sold by the cubic yard (sometimes by the ton) and is far cheaper than bags for anything more than a small bed.
- Ask what you are getting. “Screened” topsoil has had stones and roots removed; blends add compost or sand. For vegetables, a blend with organic matter is worth paying for.
- Plan the drop. A delivery of several yards is a big pile; have it tipped on a tarp close to where it is needed.
- Bags (usually 0.75 or 1 ft³) suit top-ups, containers and small beds.
Assumptions and limitations
- Weights are typical loose, moist values and vary with moisture and soil type.
- The allowance covers settling after watering; deep raised beds may settle more in the first season.
- Depth is treated as even across each area.
Topsoil questions
How much does a yard of topsoil weigh?
Usually about 1 to 1.2 tons (2,000–2,400 lb) when moist and loose. Compost is much lighter, around 0.6 tons per yard, and wet fill dirt heavier.
How many bags of topsoil make a yard?
36 bags of 0.75 ft³, or 27 bags of 1 ft³. That is why bulk soil is usually the better buy for raised beds and lawns.
How much soil do I need for a 4 × 8 raised bed?
At 12 inches deep, a 4 ft × 8 ft bed holds 32 ft³ of soil, or 1.19 cubic yards. With 15% for settling, order about 1.4 cubic yards, or 50 bags of 0.75 ft³.
How much topsoil do I need for a new lawn?
Spread 4–6 inches. For a 1,000 ft² lawn at 4 inches, that is 1,000 × 4 ÷ 324 = 12.3 cubic yards, plus settling.
Formulas, unit conversions and default values are explained on our methodology page. Results are estimates; check manufacturer data and local codes before you buy or build.