Floor Area Ratio Check Calculator

Work out floor area ratio check instantly with clear inputs, formula shown and shareable results.

About Floor Area Ratio Check Calculator

Floor area ratio is total countable floor area divided by plot area, and it is the primary control on development intensity because it is independent of building shape. The unused entitlement is the number developers watch, since it represents value that can sometimes be transferred or purchased.

Formulas

Floor area ratio

FAR = total countable floor area / plot area

Entitlement

Permitted floor area = plot area x permitted FAR

Worked example

With the default values below, Floor Area Ratio Check Calculator returns Floor area ratio achieved of 2.5000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Plot areaminimum 0.1 m²: 2,000 m²
Total floor area proposedminimum 0 m²: 5,000 m²
Permitted floor area ratiominimum 0.1: 2.5

Results

Floor area ratio achieved: 2.5000
Floor area permitted: 5,000.0 m²
Unused floor area entitlement: 0.0 m²
Compliance: Within the permitted floor area ratio

Step by step

1Values used
2Floor area ratio
3Entitlement
4Floor area ratio achieved= 2.5000
5Floor area permitted= 5,000.0 m²
6Unused floor area entitlement= 0.0 m²
7Compliance= Within the permitted floor area ratio

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Preliminary estimate only. Countable area definitions and permitted ratios must be confirmed against local development control regulations.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Preliminary estimate only. Countable area definitions and permitted ratios must be confirmed against local development control regulations.

Frequently Asked Questions

How is the Floor Area Ratio Check figure worked out?

FAR = total countable floor area / plot area. Floor area ratio is total countable floor area divided by plot area, and it is the primary control on development intensity because it is independent of building shape.

What floor area is countable?

It varies by jurisdiction. Basements used for parking, service floors, stilt areas and some balconies are commonly excluded, so the countable area can be well below the built area.

What values do I need to enter?

This calculator takes 3 inputs: Plot area, Total floor area proposed, Permitted floor area ratio. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.