Topsoil Calculator
Estimate how much topsoil a lawn, garden bed, or leveling project needs. Enter the area and desired depth to get cubic feet, cubic yards, bag counts, and optional cost.
Results
Enter your measurements to see an estimate.
Calculated: — EasyBuildTools, www.easybuildtools.com
How to use the Topsoil Calculator
Pick an area shape and enter the dimensions in feet, or use custom square footage for an irregular area. Enter the soil depth in inches, choose a bag size (or set a custom bag volume), and optionally add a waste allowance and your local prices. The tool returns square footage, cubic feet, cubic yards, an estimated bag count, and optional cost.
Formula and methodology
- Area — rectangle: length × width. Circle: π × (diameter ÷ 2)². Custom: the value you enter.
- Cubic feet = area × (depth ÷ 12) × (1 + waste% / 100).
- Cubic yards = cubic feet ÷ 27.
- Bags = cubic feet ÷ bag volume, rounded up to a whole bag.
Cost is computed from the prices you enter. If you supply a cost per cubic yard, the tool multiplies the cubic-yard total; if you supply a cost per bag, it multiplies the rounded bag count.
Worked example
Lawn strip: 20 ft × 10 ft = 200 sq ft, 4 in depth, 10% waste. Cubic feet = 200 × (4 ÷ 12) × 1.10 = 73.3 cu ft. Cubic yards = 73.3 ÷ 27 = 2.71 cu yd. With 2 cu ft bags: 73.3 ÷ 2 = 36.7, rounded up to 37 bags. Enter the values above to confirm.
Why depth, settling, and ground matter
Topsoil is sold by volume, but the depth you spread it at drives the total. A 2-inch topdressing needs half as much as a 4-inch layer over the same area. Because topsoil settles and compacts after spreading, and because few lawns or beds are perfectly flat, the calculated volume is a starting point. A 5 to 10% allowance covers settling and uneven ground; sloped or deeply rutted areas may need more.
For raised beds, a dedicated tool handles bed dimensions and optional soil-mix planning: see the Raised Bed Soil Calculator. For bulk versus bagged decisions, read Bulk Topsoil vs. Bagged Soil, and for depth and coverage basics see How Much Topsoil Do I Need?