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Find out exactly how much topsoil you need — in cubic yards, cubic feet, bags or bulk — for a lawn, garden bed, raised bed or levelling job. With depth recommendations, soil-type weights and a bulk-vs-bagged cost comparison.
A topsoil calculator estimates how much soil you need based on the area's dimensions and the depth you want. It multiplies length × width × depth to find the volume, converts it into cubic yards, cubic feet, cubic meters or bags, and also estimates weight, cost and a waste allowance for settling.
Multiply length × width × depth in feet, then divide by 27 to get cubic yards. A 10 × 10 ft bed at 6 in deep is 10 × 10 × 0.5 = 50 ft³ ÷ 27 = 1.85 cubic yards. One cubic yard covers about 54 ft² at 6 inches deep.
Worked example — a 10 × 10 ft garden bed at 6 inches. Convert the depth: 6 ÷ 12 = 0.5 ft. Volume = 10 × 10 × 0.5 = 50 ft³, which is 50 ÷ 27 = 1.85 yd³. That's about 36 bags of 40 L, weighs roughly 2.0 tons as screened topsoil, and with 10% for settling you'd order about 2.04 yd³.
Why soil type matters. The same 1.85 yd³ weighs about 2.0 tons as screened topsoil but only 1.3 tons as a compost blend — a difference that decides whether your trailer can legally carry it.
| Project | Depth | Why |
|---|---|---|
| Lawn topdressing | ¼–½ in | Thin layer — never smother the grass |
| Yard levelling | 2–4 in | Fill low spots, re-grade gently |
| New lawn / turf | 4–6 in | Root zone for establishing grass |
| Garden / flower bed | 6–8 in | Room for most perennials and annuals |
| Vegetable garden | 10–12 in | Deep roots, heavy feeders |
| Raised bed | Full depth | Usually 10–12 in; fill to the top rail |
| Tree planting | 12–18 in | Backfill the planting hole |
| Depth | Covers |
|---|---|
| 1 in | 324 ft² |
| 2 in | 162 ft² |
| 3 in | 108 ft² |
| 4 in | 81 ft² |
| 6 in | 54 ft² |
| 12 in | 27 ft² |
| Type | lb / yd³ | Tons |
|---|---|---|
| Compost blend | 1,400 | 0.70 |
| Organic mix | 1,500 | 0.75 |
| Garden soil | 1,800 | 0.90 |
| Lawn soil | 2,000 | 1.00 |
| Screened topsoil | 2,200 | 1.10 |
| Sandy loam | 2,400 | 1.20 |
| Clay blend | 2,700 | 1.35 |
| Bag size | Volume | Bags per yd³ |
|---|---|---|
| 20 L | 0.71 ft³ | 39 |
| 25 L | 0.88 ft³ | 31 |
| 40 L | 1.41 ft³ | 20 |
| 50 L | 1.77 ft³ | 16 |
| 1 cu ft | 1.00 ft³ | 27 |
| 2 cu ft | 2.00 ft³ | 14 |
1.85 yd³ · 50 ft³ · 36 × 40 L bags · ~2.0 tons
3.70 yd³ · 100 ft³ · bulk delivery territory
1.19 yd³ · 32 ft³ · 23 × 40 L bags
1.48 yd³ · 40 ft³ · ~1.6 tons screened
7.11 yd³ · 192 ft³ · order bulk, definitely
0.97 yd³ · 26.2 ft³ · 19 × 40 L bags
7.41 yd³ · 200 ft³ · spread and rake
3.09 yd³ · thin layer over 2,000 ft²
Topsoil is the upper layer of soil — typically the first 5 to 10 inches — where organic matter, microbial life and nutrients are concentrated. It's what plant roots actually live in. The subsoil beneath it is denser, poorer and much less hospitable, which is why builders scraping topsoil off a lot leaves gardens that struggle for years. Buying topsoil is essentially buying back a growing medium.
Every calculation is the same: area × depth. Measure the bed, decide how deep the soil should be, convert everything to feet, multiply, then divide by 27 to get cubic yards — the unit topsoil is sold in for bulk delivery. The step people get wrong is depth: 6 inches is 0.5 feet, not 6. Enter it wrong and your order is off by a factor of twelve.
Depth drives cost more than area does, because doubling the depth doubles the volume. Topdressing an existing lawn needs only a quarter to half an inch — any more and you smother the grass you're trying to help. A new lawn wants 4 to 6 inches of decent soil for roots to establish. Flower and garden beds are comfortable at 6 to 8 inches. Vegetables, with their deeper roots and heavier feeding, want 10 to 12. Raised beds are simply filled to their internal depth. Choose a project preset above and the calculator sets a sensible default for you.
Screened topsoil has been passed through a mesh to remove rocks, roots and debris — it's uniform, easy to rake and what you want for beds and lawns. Unscreened is cheaper and rougher, fine for bulk filling and rough grading where appearance and texture don't matter. If you're planting into it, pay for screened; the labour you save picking rocks out is worth more than the difference.
These get used interchangeably at the store and they shouldn't be. Topsoil is mineral soil — the bulk filler and structure. Garden soil is topsoil amended with organic matter, formulated for planting. Compost is decomposed organic matter: a superb amendment, but a poor standalone growing medium, since it shrinks dramatically as it breaks down and holds too much water. The usual advice for filling a bed is a blend — roughly 60% topsoil to 40% compost — rather than either alone.
Soil is heavy and the type changes it a lot. A cubic yard of screened topsoil runs about 2,200 lb — over a ton. A compost blend is closer to 1,400 lb; a clay blend can hit 2,700. Moisture adds more still, and wet soil after rain can be dramatically heavier than the same soil dry. This matters if you're borrowing a trailer or a half-ton pickup: two cubic yards of wet topsoil can exceed what many light vehicles are rated to carry.
Bags win for small, precise jobs — a couple of containers, a single raised bed, anything under roughly half a cubic yard. Beyond that the economics flip hard. One cubic yard is about 20 bags of 40 litres, which is a lot of lifting, a lot of plastic, and typically far more money than the same soil delivered loose. Bulk delivery has a fee, so the crossover depends on your local prices — the cost panel above shows both totals side by side so you can see exactly where your project lands.
Order the exact number and you'll come up short. Soil settles once watered, compacts under its own weight, and the ground you're filling is never as level as it looks. Add 5–10%. Beds filled with a high proportion of compost settle even more as the organic matter breaks down, so plan to top them up in the following season regardless.
The recurring ones: forgetting to convert inches to feet, topdressing a lawn far too thickly, filling a bed with pure compost, ignoring the weight when hiring a trailer, buying bags for a job that clearly wants a truck, and dumping good topsoil on top of compacted subsoil without loosening it first — which just creates a shallow bathtub for roots. Loosen the base, blend the layers, and the soil you bought will actually work.
A topsoil calculator estimates how much soil you need based on the area's dimensions and the depth you want. It multiplies length by width by depth to find the volume, then converts it into cubic yards, cubic feet, cubic meters or bags, and can also estimate weight, delivery cost and a waste allowance.
Multiply the length by the width by the depth, all in feet, to get cubic feet, then divide by 27 to get cubic yards. For example, a 10 by 10 foot bed at 6 inches deep is 10 x 10 x 0.5 = 50 cubic feet, which is 50 divided by 27, or about 1.85 cubic yards.
It depends on the project. Topdressing an existing lawn needs only a quarter to half an inch. A new lawn wants 4 to 6 inches of good soil. Flower beds do well at 6 to 8 inches, vegetable gardens at 12 inches, and raised beds are filled to their full depth, usually 10 to 12 inches.
Screened topsoil weighs roughly 2,200 pounds per cubic yard, or about 1.1 tons, though moisture changes it significantly. Compost blends are lighter at around 1,400 pounds, garden soil around 1,800, and heavy clay blends can reach 2,700 pounds per cubic yard. Wet soil can weigh considerably more than dry.
One cubic yard equals 27 cubic feet. A 40 litre bag holds about 1.41 cubic feet, so you need roughly 20 bags per cubic yard. A 1 cubic foot bag needs 27 bags per yard, and a 2 cubic foot bag needs 14. Buying in bulk is almost always cheaper beyond a yard or two.
One cubic yard covers about 324 square feet at 1 inch deep, 108 square feet at 3 inches, 81 square feet at 4 inches, 54 square feet at 6 inches, and 27 square feet at 12 inches deep. Simply divide 324 by your depth in inches to get the coverage.
Bags are convenient for very small jobs, roughly under half a cubic yard, but bulk delivery is dramatically cheaper per yard once you need more. A cubic yard is about 20 bags of 40 litres, which is a lot of lifting and plastic. This calculator compares both so you can see the crossover point for your project.
No. It provides estimates based on the dimensions you enter and typical soil densities and bag sizes. Soil settles and compacts, ground is rarely perfectly level, and moisture changes weight substantially. Add a waste allowance and confirm with your supplier before ordering, especially for bulk deliveries.
Topsoil is mineral soil that provides bulk and structure. Garden soil is topsoil already amended with organic matter and formulated for planting, so it costs more per yard. For filling a large bed, many gardeners buy topsoil in bulk and blend in compost themselves, which is usually cheaper than buying pre-mixed garden soil.
It is not recommended. Pure compost holds too much water, lacks mineral structure and shrinks dramatically as it decomposes, so the bed sinks. A common approach is roughly 60 percent topsoil to 40 percent compost, which gives structure, drainage and nutrition. Expect to top up any bed as the organic fraction breaks down.
Multiply the internal length, width and depth of the bed. A 4 by 8 foot bed that is 12 inches deep needs 4 x 8 x 1 = 32 cubic feet, which is about 1.19 cubic yards, or roughly 23 bags of 40 litres. Choose the Raised bed preset above and the calculator sets the depth for you.
Keep it thin — about a quarter to half an inch at a time, and never enough to bury the grass blades. Topdressing works by letting the grass grow up through a light layer, so applying too much smothers and kills it. If you need to raise the level significantly, do it gradually over several applications across seasons.
Screened topsoil has been sifted to remove rocks, roots and debris, making it uniform and easy to work, which is what you want for beds, lawns and any planting. Unscreened is cheaper and coarser, suited to bulk filling and rough grading. If you will be planting into it, screened is almost always worth the extra cost.
Use pi times the radius squared for the area, where the radius is half the diameter, then multiply by the depth. A 10 foot diameter circle at 4 inches deep is 3.1416 x 5 x 5 x 0.333 = 26.2 cubic feet, about 0.97 cubic yards. Select the Circle shape above and the calculator handles it.
Yes. The share button copies a link that encodes your dimensions, depth and options, so you can revisit the estimate or send it to a supplier or landscaper. You can also print or save the material list as a PDF. Everything runs in your browser and nothing is uploaded or stored on a server.