Build cost per m² calculator
Give a customers a fast, honest ballpark on a build — from floor area and a rate per square metre — before anyone commits to a full estimate.
Use the calculator ↓Estimate a build cost
A per-square-metre estimate for early feasibility only. Real cost depends on design, site, finishes and inclusions — price a full scope before committing.
How builders use this
Answer "roughly how much?"
When a customers asks what a build might cost, give a grounded ballpark on the spot instead of a shrug.
Test feasibility early
Before drawings and detailed pricing, check whether the budget and the brief are even in the same postcode.
Frame the contingency
Showing a contingency line sets the expectation that early numbers move as the scope firms up.
How per-square-metre estimating works
A per-square-metre rate is the quickest way to sketch a build cost early on: multiply the floor area by a rate that reflects the type and quality of construction, and you have a ballpark. Rates vary enormously with location, design complexity, finishes and inclusions, so the rate you choose matters more than the arithmetic.
A realistic estimate also carries a contingency — an allowance for the unknowns that always surface between concept and completion. This calculator applies your contingency to the base figure and adds GST to give an indicative all-in number.
This is a feasibility tool, not a quote. Once there is a design and a defined scope, a proper elemental or trade-by-trade estimate will always be more accurate than any rate per square metre.
Frequently asked questions
What cost per m² should I use?
Use a rate that reflects the construction type, quality of finish and your region — a basic build and a high-end one can differ by a factor of two or more. The rate is the biggest driver of the result, so choose it carefully.
How much contingency should I allow?
Early in a project a larger contingency is prudent because the scope is still loose; it can tighten as the design and pricing firm up. This tool lets you set whatever percentage suits the stage you are at.
Is this accurate enough to quote from?
No. It is for early feasibility only. A per-square-metre figure ignores the specifics of design, site and inclusions — always prepare a detailed estimate before quoting or committing.
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This calculator produces an indicative feasibility estimate for general information only. It is not a quote or a cost plan. Actual build cost depends on design, site, scope and finishes.