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Flooring calculator

Add up to three rooms, choose your waste allowance and box size, and get the number of boxes to buy, not just square feet.

Handy for this job

How it works

area = Σ length × width need = area × (1 + waste %) boxes = need ÷ sq ft per box, rounded up

Worked example

A 12 × 15 ft living room plus a 10 × 10 ft hall is 280 sq ft. With 10% waste you need 308 sq ft: 16 boxes at 20 sq ft each.

Tips before you buy

Buy all boxes from the same lot so color matches, and keep a spare box for future repairs. L-shaped rooms: split them into two rectangles. Closets count too.

Common questions

How much extra flooring should I buy?

10% for a straight lay in simple rooms, 15% for diagonal layouts or rooms with many corners, and up to 20% for herringbone or patterned tile.

How do I measure a room for flooring?

Measure length and width at the widest points in feet and multiply. Split L-shaped rooms into rectangles and add them together.

Should I buy an extra box of flooring?

Yes, most installers recommend keeping one spare box from the same lot for repairs.

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Estimates for planning only. Product coverage and yields vary, so check the label. Last checked 2026-10-22.