Select the unit system and display currency. Then enter net area, your rate per matching area unit, and contingency. The calculator multiplies area and rate, calculates contingency separately, and adds both.
Area and scope must match
A rate based on living area cannot be applied to gross floor area without adjustment. Record the area definition and services used by the source. Only consistently scoped rates support a useful comparison.
Finding a locally relevant cost rate
Use current bids, cost data from project professionals, or completed comparable projects. Align quality, price date, and scope with your project. The calculator deliberately loads no regional market rate.
Example
120 m² × 3,000 currency units/m² produces a base cost of 360,000. A 15% contingency is 54,000. The total estimate is 414,000 in the selected display currency.
What contingency means
Contingency is not an added scope item; it is budget for uncertainty within the chosen boundary. As design advances, it can be adjusted against identified risks. Both 0% and 100% are mathematically valid, but neither is a recommendation.
Possible gaps in the area model
Land, utilities, ground conditions, design, permits, site work, financing, taxes, escalation, and operating costs may sit outside your rate. Check every category before treating the estimate as a total project budget.
Frequently Asked Questions
Which area should I enter?
Use the net area referenced by your cost rate. Living area, usable area, and gross floor area are not interchangeable; the source and calculator must use the same definition.
What belongs in the cost per square metre or square foot?
That depends on the source. Check whether structure, finishes, systems, design, permits, site work, taxes, or fees are included, and keep the scope consistent across comparisons.
How high should contingency be?
It depends on design maturity, contract form, and project risks. The calculator provides no default; use an assumption agreed with project professionals and test several scenarios.
Are land and soft costs included?
Only if you deliberately include them in the area rate. Land, financing, design, permits, and ongoing costs are commonly planned separately.
How do I use another currency?
Select its code and enter the area rate directly in that currency. The calculator changes display only and performs no conversion.
Why is the estimate not a quotation?
It has no bill of quantities, location, quality specification, ground conditions, schedule, tender, or contract. A binding price requires project-specific planning and bids.
