Tile Calculator Formula

Understand the math behind the tile calculator. Each variable explained with a worked example.

Formulas Used

Floor Area

total_area = floor_area

Tiles (no waste)

tiles_no_waste = ceil(floor_area / tile_area_sqft)

Tiles Needed

tiles_with_waste = ceil(floor_area / tile_area_sqft * (1 + waste_percent / 100))

Boxes (approx, 10 tiles/box)

boxes = ceil(floor_area / tile_area_sqft * (1 + waste_percent / 100) / 10)

Variables

VariableDescriptionDefault
area_lengthArea Length(feet)12
area_widthArea Width(feet)10
tile_lengthTile Length(inches)12
tile_widthTile Width(inches)12
waste_percentWaste Factor(%)10
floor_areaDerived value= area_length * area_widthcalculated
tile_area_sqftDerived value= (tile_length * tile_width) / 144calculated

How It Works

How to Calculate Tiles Needed

Formula

Tiles = Floor Area / Tile Area × (1 + Waste %)

Convert tile dimensions from inches to feet (divide by 12) to get tile area in sq ft, then divide the total floor area by the tile area. Add 10% waste for straight layouts and 15% for diagonal layouts.

Worked Example

A 12 ft by 10 ft bathroom floor with 12×12 inch tiles and 10% waste.

area_length = 12area_width = 10tile_length = 12tile_width = 12waste_percent = 10
  1. 01Floor area = 12 × 10 = 120 sq ft
  2. 02Tile area = 12 × 12 / 144 = 1.00 sq ft per tile
  3. 03Tiles needed = 120 / 1.00 = 120 tiles
  4. 04With 10% waste = 120 × 1.10 = 132 tiles

Ready to run the numbers?

Open Tile Calculator