Topsoil Calculator
Calculate how much topsoil you need for landscaping, garden beds, lawn repair, and other outdoor projects. Enter your area dimensions and desired depth to get volume in cubic yards, weight in tons, number of 40-pound bags needed, and an estimated material cost.
Area Dimensions
How to Calculate Topsoil Needed
To determine how much topsoil you need, measure the length and width of your area in feet, and decide on the depth in inches. The calculator converts these measurements to cubic yards (the standard unit for bulk soil purchases) and estimates weight based on the soil type you select. Different soil types have different densities: topsoil is heavier than compost but lighter than sand. For irregularly shaped areas, break them into rectangles, calculate each separately, and add the results together.
Topsoil Volume Formula
Volume (cu ft) = Length (ft) x Width (ft) x Depth (in) / 12
Cubic Yards = Volume (cu ft) / 27
Weight (tons) = Cubic Yards x Soil Density (tons/yd3)
Bags (40 lb) = Weight (lbs) / 40 = (tons x 2000) / 40
Estimated Cost = Cubic Yards x Price per Cubic Yard
One cubic yard equals 27 cubic feet. Most landscape suppliers sell topsoil by the cubic yard for bulk delivery, or in 40-pound bags for smaller projects. Bulk delivery is significantly more economical for projects requiring more than 2-3 cubic yards.
Example Calculation
Area: 20 ft x 10 ft, Depth: 4 inches, Soil: Topsoil
Volume = 20 x 10 x (4/12) = 66.67 cu ft
Cubic Yards = 66.67 / 27 = 2.47 yd3
Weight = 2.47 x 1.1 = 2.72 tons (5,432 lbs)
Bags (40 lb) = 5,432 / 40 = 136 bags
Estimated Cost = 2.47 x $30 = $74.07
Soil Density and Coverage Reference
| Soil Type | Density (tons/yd3) | Lbs/Cu Ft | Cost/Yd3 | Coverage at 2" | Coverage at 4" | Coverage at 6" |
|---|---|---|---|---|---|---|
| Topsoil | 1.1 | 81 | $25-35 | 162 sq ft | 81 sq ft | 54 sq ft |
| Garden Soil | 1.0 | 75 | $30-40 | 162 sq ft | 81 sq ft | 54 sq ft |
| Compost | 0.6 | 44 | $35-45 | 162 sq ft | 81 sq ft | 54 sq ft |
| Fill Dirt | 1.3 | 96 | $20-30 | 162 sq ft | 81 sq ft | 54 sq ft |
| Sand | 1.4 | 104 | $40-60 | 162 sq ft | 81 sq ft | 54 sq ft |
| Peat Moss | 0.4 | 30 | $45-60 | 162 sq ft | 81 sq ft | 54 sq ft |
| Mulch | 0.4 | 30 | $25-45 | 162 sq ft | 81 sq ft | 54 sq ft |
Coverage values are per 1 cubic yard of material. Actual coverage may vary based on settling and compaction.
Frequently Asked Questions
How deep should topsoil be for a new lawn?
For a new lawn, apply 4-6 inches of quality topsoil. This provides adequate depth for grass roots to establish. For overseeding an existing lawn, 1-2 inches of topsoil or compost is sufficient. Ensure the topsoil is free of weed seeds and debris before spreading.
Should I buy bags or bulk topsoil?
For projects needing more than 3 cubic yards, bulk delivery is more economical (typically $25-50 per cubic yard delivered). Bagged topsoil costs $4-8 per 40-lb bag, which works out to $150-300 per cubic yard. Bags are convenient for small projects and areas without truck access.
How much does a cubic yard of topsoil weigh?
A cubic yard of topsoil weighs approximately 2,000-2,400 pounds (1.0-1.2 tons) depending on moisture content and composition. Wet topsoil is significantly heavier than dry. A standard pickup truck can safely carry about 1 cubic yard of topsoil.
What is the difference between topsoil and garden soil?
Topsoil is the natural upper layer of earth, screened to remove rocks and debris. Garden soil is topsoil that has been enriched with compost, peat moss, and other organic amendments to improve nutrient content and drainage. Garden soil costs more but provides better growing conditions for plants.
How much topsoil do I need for a raised garden bed?
For a standard 4x8 foot raised bed at 12 inches deep, you need approximately 1.2 cubic yards (32 cubic feet) of soil. A 4x4 foot bed at the same depth needs about 0.6 cubic yards. Use a mix of 60% topsoil, 30% compost, and 10% perlite for optimal growing conditions.