Topsoil Calculator

Multiply the area in square feet by the depth in inches, divide by 324, and you have cubic yards of topsoil. Multiply by 1.35 for tons. A 20x10 ft area at 2 inches is 200 × 2 ÷ 324 = 1.23 cubic yards, about 1.67 tons, or 45 bags of 0.75cu ft. The 324 is 27 cubic feet in a yard × 12 inches in a foot. With the calculator's 10% settling allowance, order 1.36 cubic yards, about 1.83 tons or 49 bags, which is what the calculator above shows.

How much does topsoil cover?

One cubic yard covers 324 ÷ depth square feet. One ton covers that figure ÷ 1.35. A bag covers its cubic feet × 12 ÷ depth. A 40 lb bag holds 0.5 to 0.75 cu ft, so both sizes are shown:

How deep should topsoil be?

The project list in the calculator sets these depths. Each one starts at a figure from the published range, and you can type over it.

Almanac says 6 inches is usually plenty for a new bed laid over existing soil, and to go deeper in a raised bed for root crops like carrots and potatoes. Under sod, the 4 to 6 inches gives grass roots room to grow.

How much topsoil for 1,000 square feet?

Before any settling allowance, 1,000 sq ft needs these amounts. Costs use Lawn Love's bulk range of $10 to $50 per cubic yard, before delivery.

Lawn Love's own example, 1,000 sq ft at 4 inches, comes to about 13 cubic yards and 18 tons, close to the 4 inch row above.

Topsoil for raised beds

Almanac suggests a bed mix of 40% topsoil, 40% compost and 20% sand. Pick "Raised bed" or "New garden bed" in the calculator to get the split. A 4x8 ft bed filled 12 inches deep holds 32 cubic feet, or 1.19 cubic yards. With 10% for settling that is 1.30 yards: 0.52 topsoil, 0.52 compost and 0.26 sand. The Sand Calculator works out the sand and the Mulch Calculator handles beds that get mulch on top.

Bulk or bagged topsoil, and what it costs

Lawn Love lists these price ranges. The calculator does not fill in a price, because local prices vary. Type in your supplier's quote to compare bulk against bags for your own volume.

Top-dressing a lawn

Top-dressing is a thin layer of soil, compost or sand spread over an existing lawn. Scotts gives a layer 1/4 to 1/2 inch thick, spread evenly. Choose "Top-dress a lawn" in the calculator to start at 0.5 inch, or type 0.25 for a lighter pass. At 1/2 inch one cubic yard covers 648 sq ft, and at 1/4 inch 1,296 sq ft.

Every shape works the same way: find the area in square feet, multiply by the depth in feet to get cubic feet, then divide by 27 for cubic yards. Only the area formula changes.

• Rectangle: area = length × width.
• Circle: area = π × (diameter ÷ 2)². A circle 10 ft across is 78.5 sq ft, so 4 inches of soil is 0.97 cubic yards.
• Triangle: area = ½ × base × height, with the height measured square to the base.
• Known area: the square feet you enter.

Then: cubic feet = area × (depth in inches ÷ 12). Cubic yards = cubic feet ÷ 27. Order quantity = cubic yards × (1 + allowance ÷ 100), starting at 10%. Tons = order quantity × tons per yard. Bags = order quantity in cubic feet ÷ bag size, rounded up. Bulk cost = order quantity × price per yard. Bagged cost = bags × price per bag.

Weight uses 1.35 tons per cubic yard (2,700 lb), the same figure as the Cubic Yard Calculator. The dry option uses 1.15 and the wet option 1.6, the middle of Inch Calculator's ranges of 1.0 to 1.3 tons for dry or loose soil and 1.5 to 1.7 tons for wet or compacted soil. Bags default to 0.75 cu ft, the top of the 0.5 to 0.75 cu ft range for a 40 lb bag.

Preparing ground for a new lawn? The Sod Calculator works out how much sod the same area needs. For gravel paths and edging, use the Gravel Calculator, and to compare soil with other materials for one space, use the Cubic Yard Calculator.