Flooring Calculator
Enter each room's size and box coverage. Get how many boxes to buy.
100% in your browser - no upload, no sign-up.
Boxes needed
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Floor area
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With waste
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💡 Keep one spare box - batches vary and repairs are hard to match.
⚠️ Measure closets too - a missed closet leaves you a box short.
How to use this flooring calculator
- Enter each room's width and length in feet; add a row per room.
- Enter the coverage printed on your flooring box (often around 20 ft²) and a waste allowance.
- Read the number of boxes to buy - it updates live and rounds up to whole boxes.
How many boxes of flooring you need
Plank flooring is sold by the box, and each box covers a set number of square feet (printed on the carton - often around 20 ft², but it varies by product). The calculator adds up each room's area (width × length), adds your waste allowance, then divides by the per-box coverage and rounds up to whole boxes. Use about 8% waste for a simple straight layout and 10–15% for diagonal or herringbone patterns and rooms with lots of cuts.
Frequently asked questions
- How many boxes of flooring do I need?
- Add up your room areas, add about 10% for waste, then divide by the coverage printed on the flooring box (often ~20 ft²) and round up. A 12×12 room (144 ft²) with 20 ft² boxes needs about 8 boxes. Enter your rooms and box size above.
- How much extra flooring should I buy for waste?
- Around 8% for a simple straight layout, and 10–15% for diagonal or herringbone patterns, angled walls, or lots of doorways and closets. This calculator adds your waste percentage before counting boxes.
- Should I buy it all at once and keep a spare?
- Yes. Flooring color and grain vary between production batches (lots), so buying all the boxes together keeps the floor consistent. Keep one leftover plank or box for future repairs - matching a discontinued lot later is hard.
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