Floor Area Ratio Calculator

Work out the floor area ratio of a building on its lot and check it against a zoning maximum FAR.

LIVE CALCULATION

Floor Area Ratio

0.00

total floor area ÷ lot area

Equivalent building floor area

Project Summary

Lot Area-

Building Footprint-

Number of Floors-

Total Floor Area-

Calculation Assumptions

Lot Area-

Building Footprint-

Number of Floors-

Total Floor Area-

Computed FAR-

FAR counts all above-grade floor area. Whether basements, garages, and mechanical rooms count varies by local code. Confirm with your zoning ordinance.