Room Size Calculator
Enter your room's length and width to calculate the floor area in m² and ft². Add ceiling height for wall area and paint estimates.
Unit
How to calculate the square footage of a room
Measure the length and width of the room in feet using a tape measure, then multiply length × width to get the area in square feet. For example, a room that's 10 feet long and 12 feet wide is 120 square feet (10 × 12 = 120).
For an L-shaped room or one with alcoves, split the floor plan into two or more rectangles, calculate each section's square footage separately, then add the totals together. The calculator above does this math for you — just enter length and width, and add ceiling height if you need a wall-area estimate for paint or wallpaper.
Frequently asked questions
How do I calculate the square footage of a room?
Measure the room's length and width in feet, then multiply length × width. A room that's 10 feet by 12 feet is 120 square feet. For an L-shaped or irregular room, split it into rectangles, calculate each separately, then add the totals together.
How do I find the square footage of a room without a tape measure?
Use the calculator above with an estimate, or pace it out: an average adult stride is about 2.5 feet. Count strides across the length and width, multiply by 2.5, then multiply those two numbers together for a rough square footage.
How do I measure square feet for flooring, tile, or paint?
Calculate the room's square footage first (length × width), then add 10% extra to cover cuts, waste, and mistakes — most flooring and tile suppliers recommend this buffer. For paint, you'll also need wall height; use the ceiling height field above to get a wall-area estimate.
What's the difference between square feet and square meters?
1 square meter equals about 10.76 square feet. This calculator converts between both automatically — enter your measurements in either feet or meters and get results in the other unit instantly.
Questions about this
- Will my couch fit through the door?
Measure the door's clear opening, then compare it with the sofa's height and depth. If the smaller of those two is less than the clear opening, the sofa goes through on its side. A 36-inch door often gives only 33 to 34 inches once trim and hinges are accounted for.
- What size rug do I need for a living room?
An 8×10 ft rug suits most living rooms, and 9×12 ft once the room is larger than about 12×18 ft. Whatever the size, the rug should reach under the front legs of every seat in the group and leave a 12 to 18 inch border of bare floor.
- What is a standard ceiling height?
Eight feet (2.44 m) is the standard ceiling height in most existing American homes, and nine feet is now common in new construction. Building code sets the floor rather than the norm: the International Residential Code requires at least seven feet of clear height in habitable rooms.
- How high should you mount a TV?
Put the centre of the screen at seated eye level, which Consumer Reports puts at about 42 inches from the floor for a standard couch. On a 55-inch TV that lands the bottom edge of the screen around 28 inches up.
- How high should you hang curtains?
Mount the rod 4 to 6 inches above the window frame on an 8-foot ceiling, and 8 to 10 inches on a 9-foot ceiling. When the gap between frame and ceiling is under about 12 inches, hang midway or go straight to the ceiling instead.
- Can AI design a room from a photo?
Yes. Upload one photo and an AI design tool returns that same room restyled, keeping your walls, windows and camera angle while changing finishes, furniture and lighting. It produces a visual concept in seconds, not a measured plan or a buildable specification.
Related calculators
- Cubic Feet Calculator
Calculate room volume in cubic feet and cubic meters.
- Flooring Calculator
Calculate flooring materials needed by room dimensions.
- Rug Size Calculator
Find the right rug size for a room layout.
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