Square Footage Calculator: How Many Square Feet Is My Room?

How to calculate square footage: Multiply length × width in feet. A 12×12 room = 144 sq ft. A 10×10 room = 100 sq ft. For irregular shapes, break the area into rectangles, calculate each one, then add them together. To convert to square yards, divide by 9. To convert to square meters, multiply by 0.0929. Enter your room dimensions below for instant results.

Quick answer: Multiply room length by width to get square feet. A 12×12 room is 144 sq ft, a 10×10 room is 100 sq ft, and a 20×15 room is 300 sq ft.

Using the result for a project? Go from room area to material estimates with our carpet calculator, flooring calculator, and paint calculator.

Use this page when: you need the room, wall, garage, or yard area before pricing materials. If you are already ordering carpet, go straight to carpet calculator. If you need a measuring walkthrough first, open how to calculate square footage of a room.
in feet
in feet

Common room sizes — click to auto-fill:

How to Measure a Room

Measuring square footage is one of the most common calculations for homeowners, real estate agents, and contractors. Follow these steps for accurate measurements:

  1. Clear the area. Move furniture and obstructions so you can measure wall to wall.
  2. Measure length and width. Use a tape measure and record dimensions in feet. Include inches as decimals (e.g., 12 feet 6 inches = 12.5 feet).
  3. Multiply length by width. The result is your area in square feet.
  4. For irregular rooms: Divide the room into rectangles, calculate each area separately, and add them together.

Measuring Irregular Rooms

Most rooms aren't perfect rectangles. L-shaped rooms, alcoves, and bay windows require you to break the space into simpler shapes:

Square Footage in Real Estate

In real estate, square footage is one of the most important metrics for determining property value. Here are key things to know:

Price Per Square Foot

To calculate price per square foot, divide the total price by the total square footage. For example, a 1,500 sq ft home listed at $300,000 costs $200 per square foot. This metric is useful for comparing properties of different sizes in the same area.

Average Room Sizes in the US

Not sure if your room is standard? This table shows typical room dimensions for American homes:

Room TypeAverage Size (sq ft)Typical DimensionsNotes
Master Bedroom200-35014' x 16'Excluding walk-in closet
Standard Bedroom120-18011' x 12'Min code: 70 sq ft
Living Room250-40016' x 20'Open-plan may be larger
Kitchen150-30012' x 16'Modern trend: 200+ sq ft
Full Bathroom40-1008' x 10'Half bath: 20-30 sq ft
Dining Room150-25012' x 14'Seats 6-8 people
Garage (2-car)400-60020' x 24'Usually excluded from livable sq ft
Home Office100-20010' x 12'Growing in new builds

Square Footage Conversion Chart

Quickly convert between common area units:

FromToMultiply ByExample
Square FeetSquare Yards÷ 9900 sq ft = 100 sq yd
Square FeetSquare Meters÷ 10.764500 sq ft = 46.5 sq m
Square FeetAcres÷ 43,56010,000 sq ft = 0.23 acres
Square MetersSquare Feet× 10.76450 sq m = 538 sq ft
AcresSquare Feet× 43,5600.5 acres = 21,780 sq ft
Square YardsSquare Feet× 950 sq yd = 450 sq ft

Cost Per Square Foot by Home Project (2026)

Knowing your square footage helps you estimate project costs. Here are typical per-square-foot costs for common home improvement projects:

ProjectCost/Sq Ft200 Sq Ft RoomIncludes
Interior Paint$2-$6$400-$1,200Paint + labor (2 coats)
Carpet$3-$11$600-$2,200Material + padding + install
Hardwood Floor$6-$18$1,200-$3,600Material + install + finish
Laminate Floor$3-$8$600-$1,600Material + underlayment + install
Tile Floor$7-$25$1,400-$5,000Tile + mortar + grout + labor
Drywall$2-$5$400-$1,000Material + tape + mud + labor

Frequently Asked Questions

How do you calculate the square footage of a room?
To calculate the square footage of a rectangular room, measure the length and width in feet, then multiply them together. For example, a room that is 12 feet long and 10 feet wide is 12 x 10 = 120 square feet. For irregularly shaped rooms, divide the space into rectangles, calculate each one, and add them together.
How many square feet are in an acre?
There are exactly 43,560 square feet in one acre. An acre is roughly the size of a football field without the end zones (which is 48,000 sq ft). To convert square feet to acres, divide the square footage by 43,560.
How do you measure square feet for flooring?
Measure the length and width of each room in feet, then multiply to get square footage. Add up all rooms that need flooring. Order 10% extra to account for waste from cuts and mistakes. For diagonal or herringbone patterns, order 15% extra.
How do you convert square feet to square meters?
Divide square feet by 10.764 to get square meters. For example, 500 square feet = 500 / 10.764 = 46.45 square meters. To convert the other way, multiply square meters by 10.764.
How do you calculate the square footage of a circle?
Use the formula: Area = pi x radius squared. Measure the radius (half the diameter) in feet. For example, a circular patio with a 10-foot radius has an area of 3.14159 x 10 x 10 = 314.16 square feet.
What is the average square footage of a house in the US?
The average new single-family home in the US is approximately 2,300 square feet. This varies by region: Northeast homes average about 2,100 sq ft, while Southern homes average about 2,500 sq ft. The median existing home is smaller at about 1,800 sq ft.
How do I calculate the square footage of an L-shaped room?
Divide the L-shape into two rectangles. Measure the length and width of each rectangle separately. Calculate the area of each (length x width), then add the two areas together. For example, if one section is 10x12 ft and the other is 8x6 ft, the total is 120 + 48 = 168 square feet.