BuildRight

Tile Calculator

Area to cover divided by the area of a single tile, with a waste allowance for cuts.

Area to cover (sq ft)

Tile width (in)

Tile height (in)

Waste factor (%)

Tiles needed

111

Diagonal layouts and intricate patterns need a higher waste factor to account for extra cuts.

What you entered

Area to cover (sq ft): 100Tile width (in): 12Tile height (in): 12Waste factor (%): 10

1
Area of one tile
(12 × 12) ÷ 144= 1 sq ft
2
Area to cover with 10% waste
100 × 1.10= 110 sq ft
3
Number of tiles
110 ÷ 1= 111 tiles

Result

Tiles needed: 111

Covering 100 sq ft with 12×12 in tiles needs about 111 tiles.

Tiles needed by tile size, for common floor areas at 10 percent waste

Each count is the area plus a 10 percent waste allowance divided by the face area of one tile, rounded up, exactly as the calculator does it. Grout joints are not deducted, which slightly favors you.

Area to cover (sq ft)	12 x 12 in tiles	16 x 16 in tiles	18 x 18 in tiles	24 x 24 in tiles
40 (small bathroom)	44	25	20	11
60 (bathroom)	66	38	30	17
80 (large bathroom)	88	50	40	22
100 (small kitchen)	111	62	49	28
120 (kitchen)	132	75	59	33
150 (kitchen or entry)	165	93	74	42
200 (open floor)	221	124	98	56
300 (large floor)	330	186	147	83

The 10 percent allowance suits a straight grid layout. Diagonal, herringbone and other patterns force far more cuts and need 15 to 20 percent instead, so raise the waste factor rather than reusing these columns. Large-format tile needs a flatter substrate and generates bigger, less reusable offcuts even though the count is lower. Tile is sold by the box, so convert the count into whole boxes and buy at least one spare box beyond that: dye lots change between production runs, and a cracked tile years later is nearly impossible to match.

Layout pattern changes waste

A straight grid layout wastes the least tile; diagonal layouts, herringbone, and other patterns require more cuts and typically need a higher waste factor (15-20% instead of 10%).

Order extra for future repairs

Tile runs and dye lots change over time — buying a few extra tiles beyond your waste allowance means you'll have a matching replacement on hand if one ever cracks years down the road.

Frequently asked questions

My bathroom floor is 60 sq ft and I'm using 12x12 inch tiles — how many tiles do I need?

60 tiles for the area alone (each 12x12 tile covers 1 sq ft). Add 10% for cuts and waste: 66 tiles. For a diagonal layout, add 15-20% instead — about 69-72 tiles.

How much extra tile should I buy for waste?

10% for a simple straight grid layout. 15-20% for diagonal, herringbone, or complex patterns that require more cuts. Always buy a few extra beyond the waste factor for future repairs — matching tile lots years later is nearly impossible.

Does tile size affect how many I need?

Yes — larger tiles cover more area per piece (fewer tiles needed) but generate more waste from cuts at edges. Smaller tiles like mosaics have less cutting waste but more grout lines and longer installation time.