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Use this topsoil calculator to work out how much topsoil or garden soil you need for a lawn, a garden bed or a raised bed. Pick the shape of the area, enter its measurements and the depth of soil, then press Calculate. You will see the volume in cubic yards and cubic feet, plus a suggested order amount or the number of bags, and the results update as you change values. For a raised bed, the depth is the height of soil in the bed. Results are estimates for planning.
Enter the measurements and depth, then press Calculate to see your results.
Volume needed
Recommended order amount
cubic yards ( cubic meters)
Rounded up to the next 0.25 cubic yard.
Estimated bulk cost:
Bags needed
bags
Rounded up to whole bags.
Estimated bag cost:
Show calculation
How to use this calculator
- Choose US or Metric, then a shape. Pick Rectangle, Circle, Ring or Triangle, or choose Known area if you already know the size of the area. A typical raised bed is a Rectangle.
- Enter the measurements and depth. US sizes are in feet and Metric sizes are in meters. Decimals are fine, such as 12.5. For a raised bed, the depth is the height of soil in the bed, measured from the bottom of the bed, and feet is often the easiest unit. For a lawn, it is the thickness of the soil layer. The typed value converts when you switch between inches and feet or centimeters and meters.
- Choose how you are buying. Bulk gives an order amount in cubic yards. Bags gives the number of bags in the size you pick: 0.75, 1 or 1.5 cubic feet. Add a price if you would like a cost estimate. Open More options for several identical areas, such as three matching beds, or an extra allowance.
- Press Calculate. If anything needs fixing, every problem is listed at once. After the first calculation, the results update as you change values.
- Use the results. Open Show calculation to see the steps, and use Copy result to save everything.
Formula
Start with the area of the shape. US mode uses feet and square feet; Metric mode uses meters and square meters.
- Rectangle: length × width
- Circle: π × (diameter ÷ 2)²
- Ring: π × [(outer diameter ÷ 2)² − (inner diameter ÷ 2)²]
- Triangle: ½ × base × height
- Known area: the area you enter
US: cubic feet = area × depth in inches ÷ 12 × quantity × (1 + extra ÷ 100)
Metric: cubic meters = area × depth in cm ÷ 100 × quantity × (1 + extra ÷ 100)
A depth entered in feet is converted to inches first (× 12), and a depth in meters to centimeters (× 100).
Cubic yards = cubic feet ÷ 27, and 1 cubic foot ≈ 0.0283168 cubic meters (exactly 0.3048³ m³).
Bags = cubic feet ÷ bag size in cubic feet, rounded up to a whole bag
The order amount is the cubic yards rounded up to the next quarter yard. We divide by 27 because one cubic yard is 3 ft × 3 ft × 3 ft.
Worked example
A raised bed. A bed measures 8 ft × 4 ft inside and will be filled with soil 12 inches (1 ft) high. (12 inches is just an example.)
- Area: 8 × 4 = 32 sq ft
- Cubic feet: 32 × 12 ÷ 12 = 32 cubic feet
- Cubic yards: 32 ÷ 27 = 1.19 cubic yards, so an order amount of 1.25 cubic yards
- Bags of 0.75 cubic feet: 32 ÷ 0.75 = 42.67, rounded up to 43 bags
A lawn area. A lawn area measures 30 ft × 20 ft and will get a 4 inch layer of soil. (4 inches is just an example.)
- Area: 30 × 20 = 600 sq ft
- Cubic feet: 600 × 4 ÷ 12 = 200 cubic feet
- Cubic yards: 200 ÷ 27 = 7.41 cubic yards, so an order amount of 7.5 cubic yards
- Bags of 1.5 cubic feet: 200 ÷ 1.5 = 133.33, rounded up to 134 bags
How far does soil go?
The deeper you spread soil, the less ground it covers. This table shows the area covered by one cubic yard and by one bag of each size at each depth.
| Depth | Per yd³ | 0.75 cu ft bag | 1 cu ft bag | 1.5 cu ft bag |
|---|---|---|---|---|
| 1 in | 324 | 9.0 | 12.0 | 18.0 |
| 2 in | 162 | 4.5 | 6.0 | 9.0 |
| 3 in | 108 | 3.0 | 4.0 | 6.0 |
| 4 in | 81 | 2.3 | 3.0 | 4.5 |
| 6 in | 54 | 1.5 | 2.0 | 3.0 |
| 8 in | 41 | 1.1 | 1.5 | 2.3 |
| 12 in | 27 | 0.8 | 1.0 | 1.5 |
Common soil uses and typical depths
These depths come from university extension publications. Enter the one you choose into the calculator above. We have not listed depths for garden beds in the ground or for top-dressing an established lawn, because we could not confirm them from a source we can read and name. Check with your local extension office for those.
| Use | Depth | Source |
|---|---|---|
| New lawn (topsoil) | A minimum of 4 to 6 inches, firmed or settled depth | Penn State Extension, Lawn Establishment (updated September 2025) |
| Covering sown grass seed | Only about ¼ to ½ inch of topsoil or good-quality finished compost | University of Maryland Extension, Starting a New Lawn (updated March 2026) |
| Raised bed on a hard surface | At least 8 inches deep for leafy greens, beans and cucumbers; 12 to 24 inches deep for peppers, tomatoes and squash | University of Maryland Extension, Growing Vegetables in Raised Beds (updated March 2026) |
| Raised bed (most vegetables) | A soil-and-organic mix about 8 inches deep is described as sufficient for adequate rooting of most vegetable plants | Oregon State University Extension, Raised bed gardening (FS 270, reviewed 2024) |
For a raised bed, remember that the depth you enter is the height of soil in the bed. A bed with 12 inch sides filled to the top has a depth of 12 inches (1 ft), but a bed filled only partway has a smaller depth.
Bags
Topsoil and garden soil are commonly sold in 0.75, 1 and 1.5 cubic foot bags. We read these sizes on product pages, for example theScotts Premium Topsoil 0.75 cu. ft., theMiracle-Gro Garden Soil All Purpose 1 cu. ft.and theMiracle-Gro Organic Raised Bed & Garden Soil 1.5 cu. ft.Sizes vary by brand and store, so check the bag you are buying.
Assumptions and limitations
- The area is a flat shape with the same depth everywhere. The result is a geometric volume. For a raised bed, enter the inside length and width and the height of soil.
- Soil settles. Loose soil, especially after watering, ends up lower than the depth you place, so the finished layer may be thinner than the depth you enter. Use the extra material allowance if you want to plan for that.
- Bagged and bulk soil vary. Bags, brands and bulk suppliers differ in what they contain and how much a bag holds, so check the size printed on the bag. Bags are rounded up to whole bags.
- The result is volume only, not weight. Soil weight per cubic yard varies with the type of soil and its moisture, so ask your supplier for their weight per cubic yard if you buy by the ton.
- The bulk order amount is rounded up to the next 0.25 cubic yard, because suppliers often sell in ¼ or ½ yard steps. In Metric mode it is still shown in cubic yards, with its cubic meter equivalent.
- The extra material allowance is your own figure. We do not suggest a specific percentage.
- Results are estimates for planning. Check quantities with your supplier before ordering.
Frequently asked questions
What depth do I enter for a raised bed?
Enter the height of soil you want in the bed, measured from the bottom of the bed to the top of the soil. Depth in feet is handy here: a bed filled to 1 foot deep is 1 ft. Pick the shape of the bed (usually Rectangle), enter its inside length and width, and enter the soil height as the depth.
How many bags of topsoil are in a cubic yard?
A cubic yard is 27 cubic feet, so it takes 36 bags of 0.75 cubic foot, 27 bags of 1 cubic foot or 18 bags of 1.5 cubic foot soil. Check the size printed on the bag, because it varies by brand and product.
How much topsoil do I need for a new lawn?
Penn State Extension says a new lawn typically needs a minimum of 4 to 6 inches (firmed or settled depth) of good-quality topsoil. For a 1,000 square foot lawn that is about 12.3 to 18.5 cubic yards if the whole depth has to be brought in. Enter your lawn's area and the depth you choose in the calculator above.
How deep should the soil be in a raised bed?
It depends on the crop and on what is under the bed. University of Maryland Extension says raised beds placed on hard surfaces are fine if they are at least 8 inches deep for leafy greens, beans and cucumbers, and 12 to 24 inches deep for peppers, tomatoes and squash. Oregon State Extension describes a soil-and-organic mix about 8 inches deep as sufficient for adequate rooting of most vegetable plants.
What should I fill a raised bed with?
University of Maryland Extension (Building Raised Beds for Vegetable Gardening, updated November 2023) says to fill the bed with a mixture of compost and garden soil, or purchased topsoil, in a 1:2 or 1:1 ratio. This calculator works out the total volume that fills the bed, so use it for the whole mix and then split that volume between compost and soil using the ratio you choose.
My supplier sells topsoil by the ton. Can I use this calculator?
This calculator gives volume in cubic yards, not weight. Soil weight per cubic yard varies with the type of soil and how wet it is, and we do not have a reliable published figure to offer. Ask your supplier for their weight per cubic yard, then multiply it by the order amount.
Should I order extra because soil settles?
Loose soil settles after it is placed and watered. Penn State Extension states its new-lawn depth as firmed or settled depth. The extra material allowance, under More options, adds whatever percentage you choose. We do not suggest a specific figure.