Floor Area Ratio (FAR) Calculator
The Floor Area Ratio Calculator divides total building floor area by the lot area to give the FAR, a key zoning metric. Enter the total floor area and lot area.
Formula
FAR = Total Building Floor Area ÷ Lot Area
- A FAR of 2.0 means the total floor area is twice the lot area (e.g. two full floors).
- Local zoning codes set the maximum permitted FAR.
3,000 sq ft building on 2,000 sq ft lot
Inputs
- Total Building Floor Area: 3000 sq ft
- Lot Area: 2000 sq ft
3,000 ÷ 2,000 = 1.5 FAR.
Frequently asked questions
What does FAR mean in zoning?
Floor Area Ratio caps how much floor area you can build relative to the plot size, controlling density.