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Calculators/ Interior/Tile Calculator

Tile Calculator

Tile counts, boxes, thinset and grout for any area.

Tile Calculator
ft
ft
ft²
%

Tile is sold by the box, laid by the square foot and cut at every edge, so three different numbers matter. Always buy full boxes from the same batch: dye lots differ visibly and a later top-up rarely matches.

How this is calculated

  1. Area = length × width. Add a cutting allowance before dividing: 10% for a straight lay, 15% for diagonal or herringbone.
  2. Divide by the area of one tile for the tile count, or by the box coverage for the number of boxes.
  3. A 50 lb bag of thinset covers roughly 60 square feet with a quarter inch notched trowel, less with a larger notch for big-format tile.

Frequently asked questions

How much extra tile should I buy?

Ten percent for a straight layout, fifteen for diagonal or herringbone, and always at least one extra box to keep for future repairs from the same dye lot.

What size notched trowel do I need?

A quarter inch square notch for tiles up to 12 inches, half inch for larger format. Big tiles need full coverage, which usually means back-buttering too.

Sanded or unsanded grout?

Sanded for joints wider than an eighth of an inch, unsanded for narrower joints and for polished stone that sand would scratch.

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