Floor Area Ratio (FAR)
Floor Area Ratio (FAR) is the ratio of a building's total floor area to the area of the parcel it sits on, used by zoning codes to cap development density.
How FAR is calculated
FAR equals total building floor area divided by parcel area. A 20,000-square-foot building on a 10,000-square-foot lot has an FAR of 2.0. Zoning codes set a maximum FAR per district, which — together with setbacks and height limits — caps how much building a parcel can legally support.
Why FAR drives land value
FAR is one of the most direct levers on development yield. A higher allowed FAR means more leasable or sellable area on the same dirt, so parcels with generous FAR in strong locations command premium pricing. Developers screen FAR early to model how much they can build before underwriting a purchase.
Finding density rules in Paxiv
Paxiv maps validated zoning on every U.S. parcel and links each classification to the authoritative city or county code where FAR, height, and density limits are published — so the key yield inputs can be verified at the source in one click. The core platform is free.
Frequently asked questions
What is Floor Area Ratio (FAR)?
Floor Area Ratio (FAR) is the ratio of a building's total floor area to the area of the parcel it sits on. Zoning codes use a maximum FAR to limit development density on a given parcel.
How do you calculate FAR?
Divide the building's total floor area by the parcel's land area. For example, a 20,000-square-foot building on a 10,000-square-foot lot has an FAR of 2.0.
Why is FAR important for developers?
FAR caps how much building area a parcel can support, which directly affects development yield and land value. A higher allowed FAR lets a developer build more on the same parcel.