Topsoil Calculator

How much topsoil you need to fill or top-dress

Filling raised beds, leveling a low spot, or top-dressing a lawn all come down to the same question: how many yards, and is bagged or bulk cheaper. Enter the area and depth and the calculator returns cubic yards, a bag count, and a cost, so you order once instead of eyeballing it.

The math

Length times width gives area, times depth in feet gives cubic feet, divided by 27 gives cubic yards, the unit bulk yards use. Bagged topsoil usually comes in 40-pound bags holding about three-quarters of a cubic foot. Fresh screened soil settles, so for filling beds order around 10 to 20 percent extra so you're not topping off in a month.

How deep, by project

Topsoil, fill dirt, and garden mix are not the same

What you order changes the price and the result. Screened topsoil is sifted, dark, and good for grading and lawns. Fill dirt is cheaper subsoil for raising grade where nothing has to grow. Garden or raised-bed mix blends topsoil with compost for planting. A common raised-bed recipe is roughly 40 percent topsoil, 40 percent compost, and 20 percent coarse sand, so split your total volume across the three when you order.

What a yard of topsoil weighs and covers

A cubic yard of dry topsoil runs about 1 to 1.3 tons, heavier when it's wet or full of clay. It covers about 100 square feet at 3 inches, or 324 square feet spread thin at 1 inch for top-dressing. It takes roughly 36 of the standard 40-pound bags to make a yard, so past a yard or so bulk delivery is almost always cheaper.

Two real examples

Top-dressing a 30 by 40 foot lawn with half an inch of soil: 1,200 square feet times 0.042 feet is about 50 cubic feet, just under 2 cubic yards. Filling four 4 by 8 raised beds a foot deep is a very different order: 128 cubic feet, almost 5 yards. Same backyard, very different trucks, which is why guessing burns people here.

Bagged or bulk

Bags are fine for a bed or two and easy to handle. Once you're past about a cubic yard, bulk runs far cheaper per cubic foot even after the delivery fee, and you skip hauling three dozen bags. Price both with the cost field before you commit.

How much topsoil for a new lawn

Grass wants 4 to 6 inches of workable topsoil. If you're starting from graded subsoil or builder's clay, that's the depth to buy; if the existing soil just needs help, 2 inches tilled in changes more than 4 inches layered on top. For seeding, finish with a raked, lightly firmed surface. For sod, see the sod calculator for the grass itself.

Quick answers

What's the difference between topsoil and garden soil? Bagged "garden soil" is topsoil cut with compost and priced up. For beds, buying screened topsoil and a separate yard of compost usually beats the blend on cost.

How much does a yard of topsoil cost? $20 to $50 bulk plus delivery. Bagged works out to $70 to $200 a yard, which is why bags stop making sense past a small bed.

Screened or unscreened? Screened, almost always. The few dollars saved on unscreened comes back as rocks, roots, and clods you'll rake out by hand.