Tile Calculator

Estimate the tiles and boxes needed for a floor or wall. Enter the surface size, tile size, grout width, and waste to get a purchase count.

Surface
Tile

Calculations run entirely in your browser. Nothing you enter is sent to a server.

Results

Enter your measurements to see an estimate.

Detailed breakdown

How to use the undefined

Enter the surface length and width, then the tile dimensions and grout joint width. The grout gap is added around each tile so the count reflects real coverage. Set a waste allowance for cuts and breakage, enter how many tiles come per box, and optionally a price per box.

Formula and methodology

Surface area = length × width. Effective coverage per tile = ((tile width + grout)÷12) × ((tile height + grout)÷12), in square feet. Tiles needed = surface area ÷ coverage per tile, × (1 + waste%/100), rounded up. Boxes = tiles ÷ tiles per box, rounded up.

Worked example

Floor: 10 ft × 8 ft = 80 sq ft, 12 in tiles, 1/8 in grout, 10% waste, 12 per box. Each tile covers about 1.02 sq ft with the joint. Tiles ≈ 78.4, with waste 87 tiles = 8 boxes. Enter the values above to confirm.

Helpful measurement tips

  • Buy all boxes from the same lot number so color and size match.
  • Diagonal or patterned layouts waste more — raise the allowance to 15% or more.
  • Keep at least a few spare tiles for future repairs.

Frequently Asked Questions

How many extra tiles should I buy?
A 10% allowance suits straight layouts. Increase to 15 to 20% for diagonal patterns, many cuts, or fragile tiles.
Does grout width change how many tiles I need?
Slightly. Wider joints mean each tile covers a bit more area, so you need marginally fewer tiles.
Should I calculate by area or by tile?
By area is fine for a quick estimate, but counting tiles with the grout joint included is more accurate for ordering boxes.
How do I handle an L-shaped room?
Split it into rectangles, calculate each, and add the tile counts together before rounding to whole boxes.
Why buy full boxes?
Tiles are sold and priced by the box, and matching lots later can be difficult, so it is safest to order complete boxes.
How accurate is the estimate?
It is a planning figure. Real needs depend on layout, cuts, and breakage, so verify measurements and keep spares.
Disclaimer: Results are general estimates. Actual tile needs depend on layout, cuts, and breakage. Verify your measurements and order from a single lot.