Drainage & Earthworks
Cut and Fill Calculator
Estimates cut and fill volumes for site levelling and earthworks
Updated 26 June 2026 · Live
What this tool does
Estimates cut and fill volumes for site levelling and earthworks.
Cut and Fill Calculator — enter your cut volume ({cut_m3} m³), fill volume ({fill_m3} m³), bulking factor and compaction shrinkage to estimate the net earthworks volume: {result}.
People also use
Formula Used
How the cut and fill calculator works
Estimates cut and fill volumes for site levelling and earthworks. The calculator takes your dimensions and supplier rates, applies a standard Australian trade formula, and returns a quantity with an indicative cost. Every figure is an estimate — site conditions always move the final number.
Typical Australian drainage and earthworks wastage
Excavated soil bulks up 15–35% when lifted, so skip bin capacity fills faster than the in-situ volume suggests. Plan for a 1.25× factor when hiring away muck. Our defaults reflect common Australian trade allowances, and can be adjusted upwards for non-standard geometry or downwards where experience supports a lower figure.
What this tool does not do
It does not replace a professional quote, factor regional pricing, assess structural adequacy, or confirm National Construction Code (NCC) compliance. Those remain the responsibility of a suitably qualified designer, surveyor, or your building surveyor.
On-site considerations for cut and fill
Excavations over 1.2 m deep need shoring or battered sides — the HSE guidance on trench collapse is not optional. Check for buried services with a CAT scanner before digging.
the National Construction Code (NCC) and compliance
Foul and surface water drainage to a public sewer is governed by the National Construction Code and Sewers for Adoption. Soak wells need a permeability test (BRE 365) to size correctly. When in doubt, a pre-application enquiry to the local council can give early clarity, which tends to be less costly than retrospective correction.
Before you order
Buy plastic drainage pipe in standard 3 m or 6 m lengths with integral seal joints. Cutting short lengths on site wastes material and fittings. Cross-checking the calculator’s output against a supplier quote helps catch differences in pricing assumptions — ask for exact product specifications (grade, finish, batch number) and confirm delivery timescales against your programme.
Adjusting the defaults
Every input in this calculator is editable. Enter your own dimensions, supplier prices, and wastage allowance — the output recalculates instantly. If the defaults feel off for your region or project type, your own numbers always override them.
Using this cut and fill calculator alongside other BuildMetricLab tools
This calculator works best as part of a planning workflow. Pair the quantity with our project contingency, labour-hours, and material-cost calculators to build a complete estimate before you pick up the phone to a supplier. All BuildMetricLab tools run entirely in your browser — no sign-up, no data sent anywhere, and every formula is shown on-page so you can audit the maths.
Sources & methodology
Estimates cut and fill volumes for site levelling and earthworks. Every result is calculated from the values you enter, and all inputs are editable.
Frequently asked questions
Are cut and fill calculator results accurate enough to order materials?
Use them as a starting estimate only. Verifying the final quantity with your supplier or contractor before ordering is good practice — site conditions, wastage and cut-offs all affect the true figure.
What bulking and shrinkage factors should I use?
The calculator defaults to a bulking factor of 1.25× (loose volume after excavation) and a compaction shrinkage of 0.9 (compacted fill needs more loose material to achieve the same in-place volume). Actual factors vary by soil type — sandy soils bulk less, clays can bulk more — so confirm figures with your geotechnical report or contractor before ordering.
Does this replace professional advice?
No. This tool is a planning estimator. For works that affect structure, the National Construction Code (NCC), boundary or dividing-fence, gas, electrics, drainage to a sewer, or similar, consult a suitably qualified professional.
Should I use in-situ or bulked volumes when ordering trucks?
This calculator's cut and fill inputs are in-situ / compacted volumes. The secondary results show the bulked (loose) cut volume and the loose fill volume needed, which are the figures relevant for truck loads and tipping — use those when discussing quantities with your excavation contractor.
Spotted something off?
Calculations or display — let us know.
Related tools
Calculators from other categories that planners often reach for next.