How to measure for your topsoil project
- Measure the area. Measure length × width in feet for rectangular beds or lawns. For an L-shaped or irregular area, split it into rectangles, calculate each one, and add the results. If you're topdressing an existing lawn, measure only the sections that need soil, not the whole yard.
- Choose a depth. Depth drives the volume: use ¼–½ inch for lawn topdressing, 4–6 inches for a new lawn or garden bed fill, and 6–12 inches for raised beds or deep-root planting. When in doubt, err on the side of deeper — you can always add mulch on top, but you can't easily add soil under an established bed.
- Read the result and decide: bags or bulk. You'll get cubic yards and tons. Below about 1 cubic yard, bagged topsoil (sold in 0.75–1.5 cu ft bags) is the practical choice. Above 1 yard, a loose bulk delivery — ordered by the yard — is significantly cheaper. Always order about 10% extra to account for settling and uneven subgrade.
How the topsoil calculator works
Topsoil is ordered by volume, so the formula converts your area and depth into cubic yards. First, multiply the area in square feet by the depth in inches to get inch-square-feet, then divide by 324 (which is 12 inches × 27 cubic feet — the two unit conversions rolled into one constant): cubic yards = (area_sqft × depth_in) ÷ 324. Weight is then a straight multiplier: tons = cubic yards × 1.08, because a typical bulk topsoil delivery weighs about 1.08 tons per cubic yard. Example: a 200 sq ft bed at 4 inches — (200 × 4) ÷ 324 = 800 ÷ 324 = 2.47 cubic yards, and 2.47 × 1.08 = 2.67 tons. That same project in bags would take about 89 of the common 0.75 cu ft bags (2.47 × 27 ÷ 0.75), making bulk delivery the clear value at that quantity.
Which type are you estimating?
Screened topsoil — leveling and lawn repair
Fine-screened topsoil with rocks and debris removed is the standard choice for filling low spots, regrading a yard, or patching bare areas before seeding. Depth is "as needed" to bring low spots to grade, typically 1–3 inches over most of the area. Screened topsoil blends easily with existing soil and provides a smooth seedbed.
Enter: Enter the patchy area in sq ft; set depth to 1–3 in for light grading. Order ~10% extra for uneven spots.
Garden bed or topsoil-compost blend — planting beds
A 50/50 topsoil-compost blend is ideal for in-ground vegetable or flower beds. Most vegetables need at least 6 inches of loose, amended soil to root well. For heavy clay or sandy native soil, work the blend into the top 6–8 inches. Calculate the area of the bed only — not the paths between beds.
Enter: Enter the bed area in sq ft; set depth to 6 in minimum (8 in for root vegetables like carrots).
Raised bed fill
Raised beds are filled entirely with purchased soil, so volumes are larger than they look. A standard 4 × 8 ft bed at 12 inches deep needs about 1.19 cubic yards; a 4 × 12 ft bed at 12 inches needs about 1.78 cubic yards. A quality raised-bed mix (topsoil + compost + aeration) is worth the premium — it drains and roots better than plain topsoil.
Enter: Enter the interior bed footprint in sq ft; set depth to 6–12 in depending on bed height.
Lawn topdressing
Topdressing spreads a very thin layer of topsoil or compost (¼–½ inch) over an established lawn to improve soil structure and fill micro-depressions without smothering the grass. At ½ inch, 1,000 sq ft needs about 1.54 cubic yards. Use finely screened topsoil or straight compost so it sifts between grass blades easily.
Enter: Enter the lawn area in sq ft; set depth to 0.25–0.5 in. Bag or small bulk delivery usually suffices.
Fill dirt — large-scale grading
For major grade changes (filling a low yard, building up a slope, or establishing rough grade before finish grading), unscreened fill dirt is far cheaper per yard than screened topsoil. Use fill dirt for the bulk of the volume, then cap with 4–6 inches of screened topsoil for the finish layer where plants or grass will grow.
Enter: Enter the full volume area and total depth; subtract the 4–6 in topsoil cap when ordering fill dirt.
Tips & ways to save
- Order about 10% more than your calculated amount — topsoil settles after watering and compaction eats into the depth faster than you expect.
- Bulk delivery (loose by the cubic yard) is almost always cheaper than bags once you need more than about 1 cubic yard. At 2.47 yards, the price difference is typically $80–$150 or more depending on your market.
- For irregular or oddly shaped areas, break the space into rectangles, calculate each section separately, and add them together before entering a single total area.
- Wet topsoil is significantly heavier than dry — the 1.08 tons/yard figure is for typical moisture. If your delivery arrives after rain, expect the truck weight to be higher and account for it when planning unloading access.
- Screened topsoil is worth the small premium over unscreened fill for any finished surface where you'll be planting or seeding — rocks and clods make grading and germination far harder.
Topsoil (cubic yards) by area and depth
| Area | 1 in (top-dressing) | 3 in | 6 in (new bed) |
|---|---|---|---|
| 100 sq ft | 0.31 cu yd | 0.93 cu yd | 1.85 cu yd |
| 250 sq ft | 0.77 cu yd | 2.31 cu yd | 4.63 cu yd |
| 500 sq ft | 1.54 cu yd | 4.63 cu yd | 9.26 cu yd |
| 1,000 sq ft | 3.09 cu yd | 9.26 cu yd | 18.52 cu yd |
Topsoil weighs roughly 1.08 tons per cubic yard, so the cubic-yard and ton figures are nearly the same. Order about 10% extra for settling.
Frequently asked questions
How many bags of topsoil are in a cubic yard?
How much topsoil do I need to level a lawn?
How much does a yard of topsoil weigh?
How much topsoil do I need for a raised bed?
Should I use topsoil or compost to topdress my lawn?
How do I measure an irregular area for topsoil?
Sources
Related calculators
Reviewed by the BackyardCalc editorial team. Figures are computed from the formula above and checked against manufacturer yields.