Excavation Calculator
Estimate how much soil you'll dig out for a pit, trench or footing — in cubic yards, cubic feet and cubic meters. Add a swell factor for loose (hauled) volume, truck loads to remove it, and optional dig & haul costs.
Rectangular volume = length × width × depth.
Loose soil expands when dug. Typical: sand ~12%, common earth ~25%, clay ~30%, rock ~50%.
A standard tandem dump truck typically holds 10–14 cubic yards.
Total cost = (bank cu yd × dig rate) + (truck loads × haul rate).
| Measure | Value |
|---|---|
| Calculate to see all conversions | |
How to use the excavation calculator
Four quick steps turn a hole into numbers you can order against — cubic yards in the ground, cubic yards in the truck, loads to haul it, cost, and a downloadable PDF.
Pick the shape
Rectangular pit, trench, or round hole — the fields relabel to match.
Enter the dimensions
Feet, yards, or meters, plus how many identical excavations you’re digging.
Set swell and truck size
The swell factor turns dig volume into haul volume, and truck capacity turns that into trips.
Read results & save a PDF
Volume in every unit, loads, weight, cost, and a to-scale drawing of the dig.
How excavation volume is calculated
Two calculations run here: the size of the hole, and the larger pile that comes out of it. Bank volume is what you dig; loose volume is what you haul. Here is the exact math.
Worked example — a 20 × 15 × 4 ft pit in common earth
Bank volume: 20 × 15 × 4 = 1,200 cu ft
Cubic yards: 1,200 ÷ 27 = 44.4 cu yd
Cubic meters: 1,200 × 0.0283168 = 34.0 cu m
Loose at 25% swell: 44.4 × 1.25 = 55.6 cu yd
Truck loads at 10 cu yd: 55.6 ÷ 10 = 5.6 → 6 trips
Approximate weight: 44.4 × 1.35 = 60 tons
≈ 44.4 cu yd dug, 55.6 cu yd hauled, 6 truck loads, about 60 tons of soil.
The hole never changed size — only the material did. Two extra round trips is real money on a job with a long haul to the disposal site, which is why the swell factor is worth getting right before the trucks are booked.
Excavation volume & hauling charts
The lookups that come up when pricing a dig — common pit sizes, trench volume per linear foot, swell by material, what each vehicle carries, and the unit conversions behind it all.
| Excavation | Cubic feet | Bank cu yd | Loose @ 25% | 10 cu yd loads |
|---|---|---|---|---|
| 8 × 4 × 4 ft | 128 cu ft | 4.7 cu yd | 5.9 cu yd | 1 |
| 10 × 10 × 2 ft | 200 cu ft | 7.4 cu yd | 9.3 cu yd | 1 |
| 20 × 15 × 4 ft | 1,200 cu ft | 44.4 cu yd | 55.6 cu yd | 6 |
| 30 × 20 × 5 ft | 3,000 cu ft | 111.1 cu yd | 138.9 cu yd | 14 |
| 24 × 24 × 8 ft | 4,608 cu ft | 170.7 cu yd | 213.3 cu yd | 22 |
| 40 × 30 × 6 ft | 7,200 cu ft | 266.7 cu yd | 333.3 cu yd | 34 |
Loads are rounded up, because a part-full truck is still a truck and still a round trip.
| Trench size | Cu ft per linear ft | Bank cu yd per 100 ft | Loose @ 25% |
|---|---|---|---|
| 12 in × 18 in | 1.5 cu ft | 5.6 cu yd | 6.9 cu yd |
| 12 in × 24 in | 2.0 cu ft | 7.4 cu yd | 9.3 cu yd |
| 18 in × 24 in | 3.0 cu ft | 11.1 cu yd | 13.9 cu yd |
| 18 in × 36 in | 4.5 cu ft | 16.7 cu yd | 20.8 cu yd |
| 24 in × 36 in | 6.0 cu ft | 22.2 cu yd | 27.8 cu yd |
| 24 in × 48 in | 8.0 cu ft | 29.6 cu yd | 37.0 cu yd |
| 36 in × 60 in | 15.0 cu ft | 55.6 cu yd | 69.4 cu yd |
Vertical walls assumed. Sloping or benching a deep trench widens it at every level above the base and can add a third or more to these figures.
| Material | Typical swell | 100 bank cu yd becomes | What to watch |
|---|---|---|---|
| Dry sand | ~12% | 112 cu yd | Flows out of the bucket, re-compacts readily |
| Gravel | ~13% | 113 cu yd | Heavy per yard — trucks may cap on weight |
| Common earth / loam | ~25% | 125 cu yd | The default assumption in this calculator |
| Wet clay | ~30% | 130 cu yd | Sticks in the bucket and hauls very heavy |
| Shale / soft rock | ~40% | 140 cu yd | Slower digging, more machine time |
| Blasted rock | ~50% | 150 cu yd | Biggest hauling penalty of anything on site |
Ranges, not constants. Moisture content moves these figures more than anything else, so confirm with whoever is doing the digging.
| Equipment | Typical capacity | Trips per 100 loose cu yd |
|---|---|---|
| Wheelbarrow | 3 cu ft (0.11 cu yd) | ~900 |
| Pickup truck (½ ton) | 2.5 cu yd | 40 |
| Single-axle dump | 5 cu yd | 20 |
| Tandem dump truck | 10–14 cu yd | 7–10 |
| Tri-axle dump truck | 15–18 cu yd | 6–7 |
| 20 yd roll-off dumpster | 20 cu yd | 5 |
Weight limits often bite before volume does. A tandem rated at 14 cubic yards may legally carry only 10 of saturated clay.
| Convert | Multiply / divide | Where it’s used |
|---|---|---|
| Cu ft → cu yd | ÷ 27 | How US excavation is quoted |
| Cu ft → cu m | × 0.0283168 | Metric plans and specs |
| Cu yd → cu m | × 0.7646 | Converting a US quantity to metric |
| Cu m → cu yd | × 1.308 | Reading a metric drawing |
| Cu ft → US gallons | × 7.481 | Ponds, sumps, and water features |
| Bank cu yd → tons | × 1.35 | Weight-based disposal tipping fees |
Disposal sites bill by weight or by volume depending on the facility — check which before comparing two quotes.
Every figure here describes a clean box, cylinder, or trench with vertical walls and a flat bottom — which is the shape a calculator can compute, not always the shape a machine can safely dig.
- Sloping adds volume fast — laying both walls back widens the cut at every level above the base, and the deeper the dig, the bigger the addition.
- Measure depth from finished grade — not from the top of a spoil pile or a high spot, or the whole quantity drifts upward.
- Footings need working room — real foundation digs are over-excavated beyond the concrete line so crews can form and strip the forms.
Everything the calculator works out
One set of dimensions gives you the full picture — what comes out of the ground, what goes in the truck, how many trips it takes, and what it costs.
The figures behind every excavation estimate
Built for anyone pricing a hole in the ground
A backyard pond, a run of drainage trench, or a full basement dig — the same three dimensions drive the quantity, the trucks, and the bill.
Sizing a pond, a footing, or a French drain, and working out whether the spoil fits in a dumpster or needs a truck.
- Check the wheelbarrow count before committing
- Price a dumpster against a haul-off
- Call 811 before breaking ground
Turning a dig into cubic yards, truck trips, and a defensible line item before the quote goes out.
- Set swell to the actual material
- Bid the bank, haul the loose
- Attach the PDF to the estimate
Budgeting a basement or foundation excavation and planning where the spoil goes — stockpiled, backfilled, or trucked off.
- Add over-excavation for working room
- Subtract what you’ll reuse as backfill
- Confirm disposal fees by weight or volume
7 tips for estimating an excavation accurately
Small habits that keep a dig estimate honest — and stop a job from running out of trucks halfway through the afternoon.
Excavation calculator FAQ
The volume, swell, hauling, and cost questions people ask most before booking a machine.
Multiply length by width by depth, then divide by 27 to get cubic yards. A pit 20 ft long, 15 ft wide, and 4 ft deep is 1,200 cubic feet, or 44.4 cu yd.
For a round hole use π × r² × depth. For a trench the same rule applies, so a 24-inch trench dug 36 inches deep removes 6 cubic feet for every linear foot of run.
Bank volume is the size of the hole, measured in the ground before anything is disturbed. Loose volume is what that same soil occupies once dug and piled, which is always larger because digging introduces air.
The distinction matters for money. You’re usually charged to excavate the bank volume but charged to haul the loose volume, so a 44.4 cu yd hole in common earth produces about 55.6 cu yd to truck away.
The swell factor is the percentage a material expands when excavated. Dry sand swells roughly 12%, common earth about 25%, wet clay around 30%, and blasted rock can exceed 50%.
Apply it to the bank volume to get the loose volume: 100 cubic yards of common earth becomes about 125 cu yd in the truck. Getting this wrong is the most common reason a haul-off estimate comes up short.
Divide the loose volume by the truck’s capacity and round up, because a partial load still ties up a truck and a trip. A standard tandem dump truck carries roughly 10 to 14 cubic yards.
A 44.4 cu yd dig in common earth swells to about 55.6 cu yd loose, which is 6 trips in a 10 cu yd truck. Weight can cap a load before volume does on wet or heavy material, so confirm the limit with your hauler.
Typical moist earth runs about 2,700 pounds per bank cubic yard, or roughly 1.35 tons. That’s the figure used here.
Actual weight varies a great deal — dry sand is lighter, saturated clay considerably heavier, rock heavier still. Because trucks are often limited by weight rather than volume, check the real material weight before scheduling hauling on a large job.
There’s no single national figure worth quoting. Rates swing widely with region, site access, soil and rock conditions, depth, dewatering, and how far the spoil has to travel to a legal disposal site.
Get a rate from a local contractor and enter it here. The calculator applies the dig rate to the bank volume and the hauling rate to the number of truck loads, which is how most excavation work is actually billed.
Yes, and this calculator doesn’t do it for you. It assumes vertical walls and a flat base, so any slope, benching, or shoring stand-off adds volume beyond the figure shown.
On a deep trench that extra material can be substantial, since sloping both sides widens the excavation at every level above the base. Trenches five feet deep or more require a protective system under OSHA rules, so plan the wall treatment before pricing the dig.
No. This is a planning estimate built from the dimensions you enter, treating the excavation as an idealized shape with vertical walls and a level bottom.
It doesn’t account for existing grade variation, rock, groundwater, buried utilities, over-excavation for working room, or the protective systems a real dig requires. For a bid, a permit, or a plan set, use quantities from a site survey and a licensed engineer or excavation contractor — and call 811 before any digging begins.
Not an Engineering Estimate — Planning Only: This calculator computes volume, swell, hauling, weight, and cost from the dimensions and rates you enter, assuming an idealized excavation with vertical walls and a flat, level base. It does not account for sloping, benching, shoring, over-excavation, existing grade variation, rock, groundwater, buried utilities, or material that will be reused on site. Swell factors and the 2,700 lb per cubic yard weight assumption are typical values only and vary substantially with material and moisture content — verify both with your contractor or a geotechnical report. Excavation is hazardous work. Contact 811 or your local utility locating service before any digging, and note that OSHA requires a protective system for trenches five feet deep or greater. Cost figures are simple rate multiplications, not a quotation or a bid. For planning purposes only.