Flooring Calculator
The Flooring Calculator estimates the total square footage of flooring you need for any room, including a waste allowance for cuts and mistakes, and converts that into boxes if you know your product's coverage per box.
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How This Tool Works
Enter your room's length and width, adjust the waste factor if needed, and optionally enter the square footage each box of flooring covers to see exactly how many boxes to buy.
Formula & Method
Area = length × width. We add your chosen waste percentage (10% is standard) to account for cuts, then divide by your product's coverage per box, if provided, to get the number of boxes.
Example Calculation
A 15×20 ft room is 300 sq ft. With a 10% waste factor, you should buy 330 sq ft of flooring. If each box covers 24 sq ft, that's 14 boxes.
Frequently Asked Questions
How much extra flooring should I buy?+
A 10% waste allowance covers most rectangular rooms. Increase it to 15–20% for diagonal installs, herringbone patterns, or rooms with lots of angles.
What if I don't know my box coverage yet?+
Leave that field blank — the calculator will still show the total square footage you need, which you can compare against any product's listed coverage.
Should I measure closets separately?+
Yes, measure closets and alcoves as separate rectangles and add their area to your total for the most accurate estimate.
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