Excavation Volume Calculator — m to m³, truck loads, cost
How to use this calculator
Pick the excavation shape — rectangular pit, trapezoidal (battered/sloped sidewalls), circular shaft, or utility trench — then enter each dimension with its unit (m, cm or mm) and select the soil class to load its swell factor. Bank volume (in-place, undisturbed) and loose volume (after excavation, expanded) are reported in cubic metres along with hauled mass and truck loads.
Swell factor — excavated soil bulks up as it loosens. Typical bank→loose swell: clay 30-40%, sand/gravel 10-15%, topsoil 20-30%, rock 40-60%. Always size haul trucks off loose volume. Cost — disposal priced per m³ or per truck load (haul + tipping fee). For fill returned to the same excavation, see the cut and fill calculator for the net haul-off after compaction.
Saved Calculations
| Time | Shape | Soil | Bank m³ | Loose m³ | Trucks | Cost |
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How to Calculate Excavation Volume (Metric)
Earthwork is bid on two volumes: bank (in-place, undisturbed) and loose (the swelled volume that actually rides in the truck). This tool computes both in cubic metres for a rectangular pit, a trapezoidal cut with battered walls, a circular shaft (caisson, well, pier hole), and a utility trench. Each dimension takes its own unit (m, cm or mm); the soil class sets the swell factor and an approximate haul mass so you can check truck payload as well as box volume.
Swell factor and over-excavation
Excavated soil bulks up as it loosens, so Loose Volume = Bank Volume × (1 + Swell%). Typical bank→loose swell: clay 30-40%, sand/gravel 10-15%, topsoil 20-30%, rock 40-60%, shale 35-45%. Two field allowances are not auto-added: trench over-dig for sloping or shoring per EN 1997 / Eurocode 7 (use the trapezoidal shape with the real top width), and a 5-10% line-and-grade waste on machine work. When that spoil is later returned, the compaction shrink (~10-20%) means you import more bank volume than you removed — size that with the fill and backfill calculator, and net cut against fill across a site with the cut and fill calculator.
Formulas
Rectangular / Trench: L × W × D = m³. Trapezoidal: L × ((Top W + Bottom W) ÷ 2) × D. Circular: π × r² × D. Hauled mass uses an approximate in-bank density (sand/gravel ≈ 1,600 kg/m³, clay ≈ 1,700 kg/m³, rock ≈ 2,500 kg/m³); 1 tonne = 1,000 kg. Loose volume drives the truck-load count.
FAQ
How many truck loads for a basement? A 10×12×2.4 m dig = 288 m³ bank; at 25% swell = 360 m³ loose; at an 8 m³ box = 45 loads. Why use the trapezoidal shape? Geotechnical practice and EN 1997 require sloped or shored walls below ~1.5 m, which adds real volume — enter the wider top width to capture it. Bank vs loose volume? Bank is undisturbed in-ground soil; loose is the same soil after digging, expanded by the swell factor. Granular backfill or stone bedding? Price aggregate separately with the gravel and aggregate calculator, screened topsoil with the topsoil and mulch calculator, and concrete in shafts with the concrete pier calculator.
On the jobsite
2025 EU pricing runs €25–60/m³ for machine excavation in average soil, €70–130/m³ in rock, plus €10–30/tonne tipping at most inert landfills; truck hauling adds €200–400 per 8-m³ load round-trip. The #1 estimator mistake on this trade is quoting against bank volume instead of loose — an 80 m³ basement at 30% clay swell is 104 m³ in the truck, so the haul bill is 30% bigger than the dig sheet. Two other things to budget: sloping per EN 1997 on any dig deeper than ~1.5 m adds real spoil — model it with the trapezoidal shape, not a flat overdig number — and a locate stand-by day for utility marking before you break ground. For backfill against the same foundation use the fill and backfill calculator; for the slab over a finished cellar see the concrete slab calculator.
