Estimate excavation spoil volume or fill/backfill dirt volume, truck loads and cost — metric or imperial.
Preset swell and density values are planning estimates. Actual values vary with material composition, grading, moisture, excavation method and site conditions. Use project, supplier or geotechnical values when available.
Enter in-situ/bank density for excavation weight estimates. Loose bulk density differs because excavated material occupies more volume.
Optional. If entered, loads are also checked against this weight limit and the higher of the volume-based and payload-based counts is shown. Leave blank for a volume-based estimate only. Always follow your vehicle's actual rated/legal payload.
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Choose Excavation (Cut) if you're digging a hole, trench or footing and need to know how much spoil you'll generate, or Fill/Backfill if you're bringing in dirt, topsoil or roadbase to fill or raise an area. Enter your dimensions and select a material type for a typical swell or compaction factor, or enter your own. Add your truck's capacity to see how many loads you'll need, and use the Cost tab with your local prices for a material or disposal cost estimate.
Excavation volume starts with the bank volume — the volume of soil as it sits undisturbed in the ground, calculated as length × width × depth. But once you dig it up, that same material takes up more space, because it's no longer compacted together. This is called swell or bulking, and it means the loose volume you need to haul away is greater than the bank volume you calculated.
Swell factor varies by material — sandy soils swell relatively little (around 10-15%), average topsoil swells around 20-30%, and clay or broken rock can swell 35-60% or more. This calculator's presets are typical estimates; if you know your specific soil's swell factor, enter it directly.
For fill or backfill, start with your finished (compacted) volume — the area you're covering multiplied by your target depth. But loose fill material compacts down once placed and compacted, so you actually need to bring in more loose volume than your finished volume requires.
A compaction factor of around 1.15-1.25 is typical for general fill, meaning you'd need 15-25% more loose material than your finished compacted volume. Sandy fill compacts less (lower factor), while clay-heavy fill can compact more (higher factor).
Once you know your volume, divide it by your truck or trailer's capacity to estimate how many loads you'll need, rounded up to a whole number. Weight is also shown, using a typical density for your selected material — useful if you're being charged by weight (tonnes) rather than volume, or need to check a vehicle's load capacity.
The Cost tab multiplies your truck load count by a price you enter per load — this could be a fill material purchase price, or a spoil disposal/tipping fee, depending on your project. This is a simple material or disposal cost estimate; it doesn't include excavation labour, machinery hire, site access difficulty, or permits, all of which significantly affect real excavation project costs. Get a local quote for accurate project pricing.
Example 1 — Excavation (Cut). A trench 10m long, 0.6m wide and 1m deep in average topsoil (swell factor 1.25): bank volume = 10 × 0.6 × 1 = 6 m³. Loose volume = 6 × 1.25 = 7.5 m³, which needs 2 loads with a 6 m³ truck.
Example 2 — Fill/Backfill. A 20 m² garden bed filled to a compacted depth of 0.15m with topsoil (compaction factor 1.2): compacted volume = 20 × 0.15 = 3 m³. Loose fill needed = 3 × 1.2 = 3.6 m³, which fits in a single load with a 6 m³ truck.
The most common mistake is ordering or budgeting for the bank (in-ground) volume without accounting for swell, which underestimates how much material actually needs to be hauled away. The reverse mistake happens with fill: ordering only the finished compacted volume, without the extra material needed to account for compaction, leaves a project short. Another frequent error is using a single generic swell or compaction factor regardless of soil type — clay and sand behave very differently, and using the wrong figure can meaningfully skew your estimate.
This calculator estimates volume, weight and truck loads from the dimensions, material type and factors you enter. It does not assess trench safety, shoring requirements, groundwater, underground utilities, or excavation permit requirements, all of which are critical safety and legal considerations before digging — check local regulations and consult a qualified professional. Swell and compaction factors are typical reference values and can vary meaningfully from your actual site conditions and material.
Multiply length × width × depth to get the bank (in-situ) volume of material to be removed. This calculator then applies a swell factor to estimate the actual loose volume once excavated, since dug material takes up more space than it did in the ground.
Multiply the area you're filling by the depth to get volume, then convert to cubic yards. Use the Fill/Backfill tab above with your area and depth for an automatic calculation, including a compaction allowance.
When soil is excavated, it loses its natural compaction and expands in volume. As a broad planning reference this is often 15-40% depending on the material, with clay and rock typically swelling more than sand, though actual swell depends on the specific material and site conditions. This means the loose (dug) volume is greater than the original in-ground (bank) volume.
This varies widely by location, site access, soil type and disposal distance. Use the Cost tab above with your own material and disposal prices for an estimate specific to your project; get a local quote for accurate pricing.
Divide your total loose volume by your truck's capacity and round up to a whole number of loads. Enter your truck's capacity in the calculator above to get this automatically alongside your volume calculation.
Bank volume is the volume of soil as it sits undisturbed in the ground; loose volume is what that same material becomes once excavated and its particles are no longer compacted together. Loose volume is always greater than bank volume due to the swell factor.
This depends on the area and depth you're filling. Use the Fill/Backfill tab above with your area and target depth - the calculator also adds a compaction allowance, since loose fill compacts down once placed and compacted.
Loose fill material compacts down once placed and compacted, so the loose volume you bring in needs to be greater than your finished (compacted) volume - this calculator applies a compaction factor to account for that.
Roughly 1,000-1,300 kg per cubic yard (about 2,200-2,900 lb), depending on moisture content and composition - this calculator uses a typical reference density that you can adjust for your specific material.
No - it estimates volume, weight and truck loads only. Trench safety, shoring, and excavation permit requirements are governed by local regulations and should be assessed by a qualified professional before digging.
About 25% (a factor of 1.25) is a commonly used planning reference for average soil, though actual swell varies by material and site conditions - sandy soils often swell less (around 10-15%) and clay or rock often swell more (30-60%). These are broad reference ranges, not guaranteed material properties. Select a material preset above or enter your own factor if you know your soil's actual swell.