Flooring Square Footage Calculator

Worked example

With these inputs:

• Room 1 shape: Rectangle
• Room 1 width (or diameter): 10 ft
• Room 1 length (or wall height): 12 ft
• Room 1 second section width (L-shape): 5 ft
• Room 1 second section length (L-shape): 6 ft
• Room 1 doors & windows to subtract (wall): 0 sq ft
• Room 2 shape: Rectangle
• Room 2 width (or diameter): 10 ft
• Room 2 length (or wall height): 12 ft
• Room 2 second section width (L-shape): 5 ft
• Room 2 second section length (L-shape): 6 ft
• Room 2 doors & windows to subtract (wall): 0 sq ft
• Waste factor: 10 %

Buy in full boxes — round the order figure up to the next box.

How it works

<> Square footage is just length × width, in feet. The complications are shapes that are not rectangles and openings you should not tile. Rectangle: length × width. A 10 ft × 12 ft room is 120 sq ft. L-shape: split it into two rectangles and add them. A 10×12 room with a 5×6 bump-out is 120 + 30 = 150 sq ft. Circle: π × radius². A 10 ft round patio is 78.5 sq ft. Walls: width × height, then subtract each window and door opening in square feet. Measure at the widest point of the room and measure to the wall, not the baseboard — tile runs under the trim if you remove it, and stopping short leaves a visible gap. Round every measurement up to the nearest inch, never down. Once you have the total, add waste before ordering: 10% for a straight layout, 15% diagonal, 20% herringbone. See the tile waste factor guide , then convert square feet into boxes with the tiles per square foot chart or follow the full how to measure for tile walkthrough.

Frequently asked questions

How do I calculate square footage for flooring?

Multiply each room's length by its width in feet, then add the rooms together. For L-shaped spaces split the floor into rectangles and add the parts. Add 10% waste before you order tile.

Do I subtract cabinets and islands from the square footage?

Subtract permanent cabinets and islands only if you are tiling around them. Many installers tile under the appliance run so a future remodel does not leave bare subfloor.

How many square feet is a 12x12 room?

144 square feet. With a standard 10% waste factor you should buy tile for about 159 square feet.

How do I calculate wall square footage?

Multiply wall width by wall height, then subtract windows and doors. A 10 ft x 8 ft wall is 80 sq ft; take off 15 sq ft for a standard window and you tile 65 sq ft.