Tile Calculator

Tiles and boxes for a floor or wall.

How it’s calculated

Tile footprint (sq ft) = (width + grout) × (length + grout) ÷ 144. Tiles = area ÷ footprint × (1 + waste%), rounded up. Boxes = tiles ÷ tiles per box, rounded up.

Leaving grout at 0 is slightly conservative (more tiles).

Worked examples

10×10 ft floor, 12×12 in tile, 10% waste: 100 ÷ 1 = 100 tiles; +10% = 110 tiles; at 15 per box → 8 boxes.

5×8 ft bathroom, 12×24 in tile, 15% waste: 40 ÷ 2 = 20; +15% = 23 tiles.

Waste factor

Rules of thumb (not manufacturer figures): ~10% for straight layouts, ~15% for diagonal or herringbone, more for small rooms with many cuts. Keep a few spare tiles from the same lot for future repairs.

Common mistakes

• Measuring the whole room without subtracting cabinets, tubs or other areas that won’t be tiled.
• Using a straight-lay waste factor (about 10%) for a diagonal or herringbone layout.
• Buying a few boxes later: a new lot may not match in color, so buy enough at once.

FAQ

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