NSW floor space ratio calculator
Search an NSW address to fill the site area and mapped ratio, then see the maximum gross floor area or the ratio a design achieves, with a gross floor area schedule and the working shown.
Free planning tools
Free tools for NSW planning work from Plynth: a floor space ratio calculator, a zoning explainer and a granny flat rules checker that look up a site from its address, show their working and cite the legislation they follow.
Each tool runs in the browser, shows its working and links the legislation it follows. Address lookups read NSW Government planning data as a starting point; none replaces the applicable LEP, DCP or professional assessment.
Available tools
NSW granny flat rules checker
Search an NSW address for its zone, lot area and heritage, bushfire and flood mapping, answer a few questions about the lot and the proposal, and see whether a secondary dwelling is likely complying development, likely needs a development application or is not likely permitted, with every test cited.
NSW zoning explainer
Search an NSW address to see every zone on the lot, what each zone means, the Standard Instrument objectives and mandated uses behind it, and the council LEP land use table that decides the rest. Includes a reference page for every zone.
More on the way
The planning guides explain the controls these tools calculate. If a calculation you repeat by hand would make a useful tool, tell us.