Work out floor area ratio check instantly with clear inputs, formula shown and shareable results.
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.
Floor area ratio
FAR = total countable floor area / plot area
Entitlement
Permitted floor area = plot area x permitted FAR
Preliminary estimate only. Countable area definitions and permitted ratios must be confirmed against local development control regulations.
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.
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.
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.