Square Footage

Square footage measures area in square feet (ft²). One square foot equals a 1 ft × 1 ft area (12 in × 12 in = 144 square inches).

How to Calculate

• Rectangle: Length × Width (10 ft × 12 ft = 120 sq ft)
• Irregular rooms: Break into rectangles, calculate each, then add
• Circular area: π × radius² (convert to feet first)

Common Conversions

• 1 sq ft = 0.0929 sq meters
• 1 acre = 43,560 sq ft
• 1 sq yard = 9 sq ft

Uses

Real estate pricing ($/sq ft), flooring materials, painting (wall sq ft), landscaping, and HVAC sizing.

Livable vs. Gross Square Footage

Real estate listings typically count "livable" or "heated" square footage — finished, climate-controlled space — while excluding garages, unfinished basements, and porches. This is why a home's tax assessment square footage and its real estate listing square footage sometimes don't match; they're measuring by different standards (ANSI Z765 is the most common residential standard in the U.S.).

Ceiling Height and Sloped Areas

Under most measurement standards, finished areas with ceilings below 5 feet (common in attics and dormered rooms) don't count toward livable square footage at all, and areas between 5–7 feet only count partially — a frequent surprise for owners of homes with converted attic spaces.