Fill dirt, soil & backfill estimator
Estimate fill dirt, topsoil or backfill by entering length, width and depth. Adjust bulk density and compaction because wet soil, dry soil, topsoil and engineered fill can occupy and weigh very different amounts.
Interactive tool
Planning estimate only. Verify measurements, material specifications, densities, package coverage and supplier pricing before ordering.
Visual guide
See the measurement path before using the formula. The visual separates area, depth, volume and purchase units so the calculation is easier to verify.
Practical guide
The number is only useful when the inputs describe the actual project. These are the assumptions that most often change the result.
The finished hole, trench or low area gives the compacted target volume. Loose soil can settle after placement, so the calculator separates finished volume from an order quantity that includes your compaction and waste allowances.
Soil bulk density depends on texture, moisture, organic matter and compaction. Dry topsoil, wet clay and engineered fill do not weigh the same per cubic yard. The editable density field is therefore more useful than pretending one tonnage factor fits every project.
Measure the void or fill area, calculate the target volume, add a realistic compaction allowance, and then use supplier density if you need estimated tons. For structural backfill, follow the project specification for material type, lift thickness and compaction rather than relying only on a volume estimate.
Calculation guide
Calculate the finished volume first. If the material will compact, add a compaction allowance to estimate the loose quantity you should order. Multiply loose cubic yards by the entered tons-per-yard value when a weight estimate is useful.
Enter length and width for a rectangular project, or use the known-area field when you already have square footage, square yards, square metres or acres.
Use the finished layer depth you actually plan to install. The calculator converts inches, feet, centimetres or metres into a consistent volume calculation.
Area multiplied by depth gives cubic volume. The tool shows cubic feet and cubic yards so you can compare bulk supplier units without doing another conversion.
Where relevant, apply density for tons, bag size for bag counts, waste or compaction allowances, and your local unit price for an estimated material cost.
Worked example
A 20 ft × 10 ft area filled 6 inches deep is 100 ft³, or about 3.70 yd³ finished volume. With a 10% compaction allowance, the order quantity becomes about 4.07 yd³.
Reference values
Use this table for quick planning checks. Calculator inputs remain the better choice when your dimensions, depth, density, waste or product coverage differ.
| Area | 4 in Fill | +10% Compaction |
|---|---|---|
| 100 ft² | 1.23 yd³ | 1.36 yd³ |
| 200 ft² | 2.47 yd³ | 2.72 yd³ |
| 300 ft² | 3.70 yd³ | 4.07 yd³ |
| 400 ft² | 4.94 yd³ | 5.43 yd³ |
| 500 ft² | 6.17 yd³ | 6.79 yd³ |
| 600 ft² | 7.41 yd³ | 8.15 yd³ |
| 700 ft² | 8.64 yd³ | 9.51 yd³ |
| 800 ft² | 9.88 yd³ | 10.86 yd³ |
| 900 ft² | 11.11 yd³ | 12.22 yd³ |
| 1,000 ft² | 12.35 yd³ | 13.58 yd³ |
People also ask
Overlapping questions are consolidated so each answer covers a distinct calculation or planning issue.
Multiply length by width by fill depth to get volume. Convert to cubic yards and add a compaction or waste allowance if the material will settle or be mechanically compacted.
Not necessarily. Cubic yards measure volume and tons measure weight. Soil density changes with material type, moisture and compaction.
Coverage depends on depth. Two cubic yards spread 3 inches deep covers four times as much area as the same volume spread 12 inches deep.
Payload and bed capacity vary widely by truck, and soil can be very heavy. Check the vehicle payload rating and the supplier’s material weight before loading.
Truck body capacity varies by vehicle and legal payload limits. Use the supplier or hauler specification rather than assuming one universal dump-truck capacity.
Formulas are shown on the page and variable assumptions are exposed as inputs where they affect the result. Unit relationships are checked against USDA NRCS Soil Quality Indicator: Bulk Density. Material density, packaging, product coverage and pricing should be verified with the supplier for the material actually being purchased.