Tile Calculator
How many tiles you need for a floor, wall, or backsplash
What is tile calculator?
Tile count is area ÷ tile sqft × (1 + waste factor), then rounded up. A 12×12 in tile covers exactly 1 sqft; a 3×6 in subway tile covers 0.125 sqft. The widget converts tile dimensions from inches to sqft internally, so you enter nominal inches and it handles the math. The single biggest mistake DIYers make is using 0% waste on straight jobs — even a simple grid layout produces cuts at every edge, and cracked tiles during wet-saw cuts are unavoidable.
Pattern choice drives waste more than anything else. A straight-grid layout needs 10% — one tile in ten goes to cuts and breakage. Diagonal (45°) jumps to 15% because every perimeter tile gets an angled cut. Herringbone, basketweave, and offset brick patterns add 15-20%. If you’re tiling a small bathroom in herringbone, budget 20% and don’t argue with it.
Tile size selection is a substrate and scale decision. Large-format tiles (18×18, 24×24) reduce grout lines and look clean in open rooms but demand a flat substrate — any high or low spot over 1/8 in across a 10 ft span will create lippage. Small-format tiles (4×4, 6×6, mosaic sheets) forgive humps and dips better because the grout joint absorbs the variation. For rooms under 8 ft wide, stay under 16×16 in tile or the tile pattern will look out of scale.
Dye-lot discipline is non-negotiable. Buy all tiles for a job from the same dye lot in one purchase. If you run short and reorder, you will get a different firing batch, and the color shift will be visible under raking light. Calculate your count, add 10% for breakage spares, and buy that number on day one. Leftover tile stores flat in a dry space for years — it’s cheap insurance against a cracked tile in year three.
When to use a tile calculator
- Kitchen floor — A 12 × 14 ft kitchen with 12×12 in tile covers 168 sqft. At 10% waste that's 185 tiles — budget for one full extra box on top of that in case you crack a few during cuts. Most 12×12 tile comes in boxes of 15-20, so you'll buy 10-13 boxes depending on box size.
- Bathroom floor or wall — A 5 × 8 ft bathroom floor is 40 sqft. With 6×6 in tile (0.25 sqft each) and 10% waste, that's 176 tiles. Small-format tile hides imperfect substrates better than large-format but generates more grout lines — bump waste to 15% if you're setting a diagonal pattern in that small a space.
- Backsplash strip — An 8 ft × 18 in backsplash is 12 sqft. With 3×6 in subway tile (0.125 sqft each) at 10% waste, that's 106 tiles. For a full sheet-mounted mosaic, divide total sqft by the sheet coverage (usually 0.97 sqft per 12×12 sheet) instead of individual tile size.
How to use the Tile Calculator
- Measure the area — Length × width in feet. Toggle Total area if you already have sq ft from a floor plan. For irregular rooms, split into rectangles and add.
- Enter tile size — Tile length × width in inches. Common sizes: 12×12, 12×24, 18×18, 24×24. The widget converts to sqft per tile internally.
- Pick a waste factor — 10% covers cuts and breakage on a straight grid layout. Bump to 15-20% for diagonal, herringbone, or other patterns that produce more offcuts.
Worked examples
Kitchen floor: 12 × 14 ft, 12×12 tile
Input: L 12, W 14, tile 12×12 in
Output: 185 tiles (168 sqft + 10% waste)Bathroom: 5 × 8 ft, 6×6 tile
Input: L 5, W 8, tile 6×6 in
Output: 176 tiles (40 sqft + 10% waste)Backsplash: 12 sqft, 3×6 subway
Input: Total area 12 sqft, tile 3×6 in
Output: 106 tiles (12 sqft + 10% waste)