Square Footage Calculator

Square footage drives price per square foot, property tax assessments, flooring and paint estimates, and how a listing is marketed. Getting it right — and knowing which spaces officially count — prevents costly misunderstandings. This calculator converts dimensions into area and helps you reason about usable space.

Inputs

%

Add 10% for most flooring

Results

Total Area

368.0 ft²

Total Area (converted)34.2 m²
With 10% Waste Factor404.8 ft²
Rooms Measured3 rooms
More details
With Waste (m²)37.6 m²
Room 1168.0 ft²
Room 2120.0 ft²
Room 380.0 ft²

How to Use

  1. 1Select your unit of measurement (feet or meters).
  2. 2Enter the length and width of each room you want to measure.
  3. 3Leave unused room slots at 0.
  4. 4Set a waste factor (10% is standard for flooring installation).
  5. 5Use the converted area when comparing with metric floor plans.

What counts as living area

Not all square footage is equal in the eyes of appraisers and listing standards. Gross living area generally counts finished, heated, above-grade space measured from exterior walls. Basements — even beautifully finished ones — are usually reported separately as below-grade space rather than folded into the headline square footage, because they are valued differently. Garages, unfinished attics, and covered porches typically do not count as living area at all.

This distinction explains why two homes advertised at the same square footage can feel and appraise very differently. A 2,000-square-foot home with all space above grade is not the same as one counting a finished basement toward that total. When you compare listings or check an assessment, look at how the area is broken down, not just the single headline number.

Putting area to work

Accurate area measurements make everyday projects far easier to budget. Flooring, paint, tile, and materials are all sold and estimated by area, so a reliable square-footage figure — plus a sensible waste allowance of roughly 10% for cuts and mistakes — turns a guessing game into a firm shopping list. For irregular rooms, break the space into rectangles, calculate each, and add them together.

Square footage also underpins price comparisons. Dividing a home's price by its living area gives price per square foot, the standard way to compare homes of different sizes within a market. Use it as a quick sanity check, but remember it does not account for condition, location within a neighborhood, lot size, or finish quality — all of which can justify large differences between homes with identical price-per-square-foot math.

Frequently Asked Questions

How do I measure square footage for flooring?+

Measure each room's length × width, add all rooms together, and add 10% for waste (cuts and pattern matching). For irregular rooms, break them into rectangles and add the areas.

How many square feet is 1 square meter?+

1 square meter = 10.764 square feet. So a 100 m² apartment is about 1,076 sq ft. This calculator automatically converts between the two units.

Does square footage include walls and closets?+

In real estate listings, square footage is measured from interior walls and typically excludes wall thickness. Closets are included. Unfinished basement, garage, and attic are usually listed separately.

Why add a waste factor for flooring?+

When cutting tiles or planks to fit, you generate waste. For straight-lay tile or plank, add 10%. For diagonal lay or complex patterns, add 15%. For irregular rooms, add up to 20%.

What is the average size of a US home?+

The median new US home is about 2,300 sq ft (214 m²). The average apartment is 900 sq ft (84 m²). A typical 3-bedroom house runs 1,500–2,000 sq ft.

This calculator is for informational purposes only and does not constitute financial, legal, or tax advice. Consult a qualified professional before making real estate or financial decisions.