Cubic yards, bag equivalents, and cost for lawns and beds
Topsoil is sold by the cubic yard, but lawns and garden beds are measured in square feet and inches of depth — and that unit mismatch is exactly where ordering mistakes happen. This calculator converts your area and desired depth into cubic yards, estimates the weight, and prices the order from a per-yard price you enter, since delivered topsoil prices vary substantially by region and quality.
The core conversion is fixed arithmetic: volume (cu ft) = area (sq ft) × depth (in) ÷ 12, and cubic yards = cubic feet ÷ 27, because a yard is 27 cubic feet (3 ft × 3 ft × 3 ft). One yard of topsoil spread 1 inch deep covers 324 square feet; at 3 inches, 108 square feet; at 6 inches, 54 square feet. Those three numbers alone let you sanity-check any quote.
Depth should match the purpose. Overseeding an existing lawn needs a quarter to half inch; establishing new turf grass generally wants 4 to 6 inches of rootable soil; raised beds are usually filled with a blend rather than pure topsoil; and vegetable gardens commonly target 6 to 12 inches of workable soil. Deeper is not automatically better — subsoil drainage matters as much as topsoil depth.
The table below shows what one cubic yard covers at common depths, plus the bagged equivalent. Bulk topsoil typically weighs about a ton per cubic yard when reasonably moist — screenings and blends vary — which is why a 5-yard delivery arrives on a dump truck, not in a hatchback.
Bagged versus bulk is mostly a volume decision. A 40-lb bag of soil holds roughly 0.5–0.75 cubic feet depending on density and moisture, so one cubic yard equals roughly 40–55 bags. Below about a yard, bags are convenient; above it, bulk delivery wins decisively on both cost and labor.
Moisture moves the weight a lot: the same yard of topsoil can weigh anywhere from roughly 1,700 lb when dry to over a ton when saturated, and suppliers quote either way. For project logistics, what matters is the delivery: bulk loads are dumped, so plan where the pile lands (tarps protect lawns, and a pile on pavement can stain); access for a dump truck needs clearance; and any soil being graded against a foundation should slope away per standard drainage practice of about 6 inches of fall in the first 10 feet.
Quality varies as much as weight. Screened loam is the default for lawns; unscreened soil is cheaper but full of clods and roots; and 'topsoil' with no specification can be construction spoil. Ask the supplier what the soil is and where it came from — weeds, rocks, and compaction travel with the load.
| Depth | Coverage of 1 cu yd | Yards for 1,000 sq ft |
|---|---|---|
| 1 in | 324 sq ft | ~3.1 |
| 2 in | 162 sq ft | ~6.2 |
| 3 in | 108 sq ft | ~9.3 |
| 4 in | 81 sq ft | ~12.3 |
| 6 in | 54 sq ft | ~18.5 |
Round up, not down. Order to the nearest half or whole yard above your computed figure, both because depth is never perfectly uniform when spreading by wheelbarrow and because a spare bit of soil always finds a use — filling low spots, potting repairs, or the compost pile's dead zone. A 10% cushion is the usual practice, and the calculator's waste input handles it.
A worked example ties it together. Suppose you are topdressing and seeding a 30 ft × 40 ft lawn — 1,200 sq ft — with 2 inches of screened loam. Volume is 1,200 × 2 ÷ 12 = 200 cubic feet, which is 200 ÷ 27 ≈ 7.4 cubic yards; with a 10% cushion that is 8.1, so order 8 yards. At roughly a ton per yard, expect about 8 tons delivered on a single dump load, and plan two people with a wheelbarrow most of a day to spread it. If the supplier quotes by the ton instead of the yard, the same math works in reverse: divide the tonnage by roughly one ton per yard to get the yardage.
How do I calculate how much topsoil I need?
Multiply area (sq ft) by depth (inches) and divide by 12 to get cubic feet, then divide by 27 for cubic yards. A 500 sq ft lawn at 3 inches needs 500 × 3 ÷ 12 ÷ 27 ≈ 4.6 cubic yards — order 5.
How many square feet does a yard of topsoil cover?
324 sq ft at 1 inch deep, 162 at 2 inches, 108 at 3 inches, and 54 at 6 inches. These come from 27 cubic feet per yard divided by the depth in feet.
How much does a cubic yard of topsoil weigh?
Roughly a ton (about 2,000 lb) at typical moisture, ranging from around 1,700 lb dry to over a ton saturated. Weight varies with moisture and composition — suppliers quote either way, so ask.
How many bags equal a cubic yard?
A 40-lb bag holds roughly 0.5–0.75 cubic feet, so a yard is about 40–55 bags. Above roughly one yard, bulk delivery is almost always cheaper and far less labor.
How deep should topsoil be for a new lawn?
New turf establishment generally targets 4–6 inches of quality topsoil for healthy roots, while overseeding an existing lawn needs only ¼–½ inch as a topdressing. Ensure the finished grade slopes away from the foundation.