Question 1

How do I calculate how many tiles I need?

Accepted Answer

Measure the length and width of the area to tile, then multiply to get the total area. Divide by the area of one tile (length × width). Add 10-15% extra for cuts, breakage, and future repairs. For diagonal patterns, add 20% waste.

Question 2

What is the standard waste percentage for tile?

Accepted Answer

For straight (grid) patterns, add 10% for waste. For diagonal patterns or rooms with many corners, add 15-20%. Always round up to the nearest full box — tiles are sold in fixed quantities per box.

Question 3

How do I account for grout joints?

Accepted Answer

Standard grout joints are 1/8" to 3/16" (3-5 mm) for floor tiles and 1/16" to 1/8" (1.5-3 mm) for wall tiles. This calculator uses the nominal tile size, so the actual coverage may be slightly higher. The waste percentage already accounts for typical grout spacing.

Question 4

Should I buy extra tiles?

Accepted Answer

Yes. Always buy 10-15% extra to cover cuts, breakage, and future repairs. Tiles from the same dye lot can vary in color, so buy all at once. Keep a few leftover tiles for any future repairs that may be needed.