How to Use This Calculator
Enter your area length and width in feet, then set the depth in inches. For new garden beds, 6 inches is the standard starting depth. For topdressing an existing lawn, 1 to 2 inches is typical. For raised beds, measure the interior dimensions and use the actual fill depth you want. The calculator converts your inputs to cubic yards and adds a 10% allowance for settling. Results include: cubic yards to order from a bulk supplier, the equivalent number of 0.75 cu ft bags, and a low-to-high cost estimate based on typical bulk and bag pricing. For L-shaped or irregular areas, calculate each rectangular section separately and add the cubic yard totals.
How to Calculate Cubic Yards of Topsoil
The formula: Cubic Yards = (Length × Width × Depth in feet) ÷ 27. Convert depth from inches to feet by dividing by 12.
| Depth | 1 yd³ covers | Bags (0.75 cu ft) per yd³ |
|---|---|---|
| 2 inches | 162 sq ft | 36 |
| 3 inches | 108 sq ft | 36 |
| 4 inches | 81 sq ft | 36 |
| 6 inches | 54 sq ft | 36 |
| 12 inches | 27 sq ft | 36 |
Worked example: 20 × 15 lawn patch at 3 inches deep. Area = 300 sq ft. Cubic feet = 300 × (3 ÷ 12) = 75 cu ft. Cubic yards = 75 ÷ 27 = 2.78 yd³. With 10% for settling: 2.78 × 1.1 = 3.05 yd³. Order 3 yards bulk or 110 bags (0.75 cu ft).
Tips for Ordering Topsoil in Bulk
Always add extra when ordering bulk topsoil. Freshly delivered soil settles 10 to 20 percent after the first rain cycles. If you fill a raised bed flush to the top, it will sit noticeably low by next spring. The 10% allowance in the calculator is a minimum; for beds you want to stay full, add 15% to be safe.
Ask for screened topsoil when ordering in bulk. Unscreened topsoil often contains rocks, debris, and weed seeds from the excavation site. Screened topsoil has been processed through a mesh to remove these materials. The price difference is usually $5 to $10 per yard and is almost always worth it.
Check delivery access before ordering more than 2 cubic yards. Bulk topsoil arrives on a dump truck, which needs at least 10 feet of clearance and a firm surface to avoid rutting. If the truck cannot reach your project area, factor in the time and equipment needed to wheelbarrow material from the drop point. Each wheelbarrow load moves roughly 3 cubic feet, or one-ninth of a cubic yard.
What to Buy
For any project under 1 cubic yard, bags from a hardware or garden store are the most practical choice. Look for bags labeled "topsoil" or "garden soil"; check the cubic foot measurement on the label, as sizes vary from 0.75 to 1.5 cubic feet. The calculator uses 0.75 cu ft as the standard bag size.
For projects over 1 cubic yard, call local landscape suppliers for bulk pricing. Ask specifically for screened loam or sandy loam topsoil with less than 20% clay. Delivery charges vary; many suppliers include free delivery for orders over 3 cubic yards within a set radius. Compare at least two suppliers: prices vary significantly by location and season, with spring being the most expensive time to buy.