How much waste should I add for a bathroom floor?

15% is standard for a small room with lots of cuts around fixtures. Bump to 20% if the tile is laid on a diagonal or the room is smaller than 40 sq ft.

How many tiles for a 5×8 bathroom floor?

A 5×8 ft (40 sq ft) bathroom floor with 12×12 in tiles needs about 46 tiles with 15% waste — usually 5 boxes at 10 tiles per box.

Tile Calculator for a Bathroom Floor — Tiles & Boxes

How the tile calculator works

Divide the total floor area by the coverage of a single tile (tile width × height ÷ 144 for inches to ft²). Add a 10% waste factor for cuts, and divide by tiles-per-box to get boxes.

Formula: tiles = (area ÷ tile ft²) × (1 + waste%)

Popular uses for the tile calculator

Tile for a Bathroom Floor

Estimate tiles and boxes for any bathroom floor.

Tile for Shower Walls

Estimate tiles for a full shower surround.

Tile for a Kitchen Backsplash

Estimate tile and boxes for a kitchen backsplash.

Tile for a Kitchen Floor

Estimate tile and boxes for a kitchen floor.

Tile for a Laundry Room

Estimate tile and boxes for a laundry room floor.

Frequently asked questions

How much extra tile should I order?

10% for straight lay, 15% for diagonal or herringbone, 20% for complex patterns. Order attic stock to keep for repairs.

How many 12×12 tiles in a box?

Typically 10–15 per box, but always check the box label — coverage varies by manufacturer.

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