Topsoil and Fill Calculator
Find out exactly how many cubic yards of topsoil or fill dirt you need for raised beds, lawn leveling, or grading projects. Enter your area dimensions and target depth to get an instant material estimate.
About this calculator
Soil volume calculations start by finding the void — the difference between your desired depth and current soil depth — then converting that volume to cubic yards, the standard unit for bulk soil delivery. The core formula is: Volume (yd³) = (length × width × ((desiredDepth − currentDepth) / 12)) / 27. Dividing by 12 converts depth from inches to feet, and dividing by 27 converts cubic feet to cubic yards. Because soil settles and compacts after delivery, a compaction factor is applied: topsoil compacts roughly 20% (factor 1.2), mixed soil 10% (factor 1.1), and fill dirt negligibly (factor 1.0). Ordering with this factor already built in means you won't come up short after the first rain. Always measure your area carefully — a 10% error in length or width compounds into a significant volume difference.
How to use
You want to fill a raised bed that is 12 ft long × 4 ft wide. The current soil depth is 2 inches and you want 8 inches. Step 1 — depth difference: 8 − 2 = 6 inches. Step 2 — volume in cubic feet: 12 × 4 × (6 / 12) = 12 × 4 × 0.5 = 24 ft³. Step 3 — convert to cubic yards: 24 / 27 = 0.889 yd³. Step 4 — apply topsoil compaction factor: 0.889 × 1.2 = 1.07 yd³. Order at least 1.1 cubic yards to account for settling. Most suppliers sell in half-yard increments, so you would order 1.5 yd³.
Frequently asked questions
How many cubic yards of topsoil do I need for a 1000 square foot lawn?
For a 1000 sq ft lawn with a 4-inch topsoil layer, the calculation is: 1000 × (4/12) / 27 = 12.35 yd³ before compaction. Applying a 1.2 topsoil compaction factor gives approximately 14.8 yd³. A standard dump truck holds 10–14 cubic yards, so you would likely need two partial loads. Always measure your current soil depth first — if 2 inches already exist, you only need to add 2 more inches, cutting your order nearly in half.
What is the difference between topsoil and fill dirt for landscaping projects?
Topsoil is the nutrient-rich upper layer of soil (typically the top 2–8 inches) that supports plant growth, making it ideal for lawns, gardens, and raised beds. Fill dirt is subsoil — lower organic content, used purely for structural grading, leveling low spots, and building up ground elevation before laying topsoil. Fill dirt is less expensive and compacts more predictably, but plants cannot thrive in it alone. Most landscaping projects use fill dirt for bulk elevation changes, then top with 4–6 inches of quality topsoil.
Why do I need to order more topsoil than my volume calculation suggests?
Freshly delivered topsoil is loose and aerated, so it compacts by 15–20% once it settles, gets rained on, or is walked on. If you order exactly the calculated volume, you will likely end up short after the first season. The compaction factor (1.2 for topsoil) pre-accounts for this shrinkage so your finished depth matches your target. Additionally, slight measurement errors and uneven existing surfaces often mean the actual void is larger than estimated, making a small overage order a wise investment.