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Tile & Flooring Calculator
How many tiles or boxes for your floor? Enter the room and tile size — waste allowance included.
Room & tile size
How to calculate tile by hand
- Room area = length × width (in feet) → square feet.
- Tile area = (width × length) ÷ 144 (inches → sq ft).
- Tiles = room sq ft ÷ tile sq ft, then add 10–15% waste and round up.
Example: 10×12 ft room = 120 sq ft. 12×12 tiles = 1 sq ft each → 120 tiles + 10% = 132 tiles.
Tile FAQs
How much extra tile should I buy?
10% for straight layouts, 15% for diagonal or patterned layouts. Keep a few spare tiles for future repairs — dye lots change.
Do I count the area under cabinets?
For flooring under fixed cabinets or islands, you can subtract it — but many installers tile underneath anyway for a cleaner finish.
What about grout lines?
Standard grout lines (1/8″–1/4″) barely change the math. This calculator's waste allowance covers it.
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Frequently asked questions
How much extra tile should I buy for waste?
Buy 10 percent extra for straight layouts and 15 percent for diagonal or patterned layouts to cover cuts and breakage.
How do I calculate square footage for tile?
Multiply the room length by the width in feet. For L-shaped rooms, split the area into rectangles, calculate each, and add them together.
What size grout joint should I use?
Most floor tiles use a 1/8 to 3/16 inch grout joint. Larger tiles (12x24 and up) usually need at least a 3/16 inch joint.
How many tiles come in a box?
It varies by tile size and brand. Check the box label for coverage in square feet, then divide your total square footage (plus waste) by that number.