FAR

Floor area ratio is the ratio of a building's zoning floor area to the area of its zoning lot, defined in § 12-10 of the NYC Zoning Resolution. It is the city's primary control on building size: each zoning district assigns maximum FARs — often separate ceilings for residential, commercial, community-facility, and manufacturing floor area — and a lot's area multiplied by the applicable maximum sets the ceiling on how much floor area it can carry.

Analysts distinguish built FAR (what stands today, computed from records), maximum FAR (what the district allows), and residual FAR (the difference — the first approximation of development headroom). The maximum that governs a specific lot depends on use, street conditions, overlays, and special districts, so a bare FAR number without its conditions is incomplete.