Tile Calculator
How many tiles do I need? Enter the area, tile size, grout gap, and tiles per box to get a whole-tile count and boxes to buy.
Calculator
How it works
We convert the room and tile sizes to inches, add your grout gap to each tile edge, then count how many tiles fit along length and width (rounding each side up). Waste is applied to that count, then we divide by tiles per box and round up so you never buy a fraction of a box.
Formula
Tiles along length = ceil(area length / (tile length + grout)). Tiles along width = ceil(area width / (tile width + grout)). Tiles needed = those counts multiplied. Tiles with waste = ceil(tiles needed x (1 + waste%)). Boxes = ceil(tiles with waste / tiles per box).
Example
A 10 ft x 12 ft area, 12x12 in tiles, 0 grout, 10% waste, 20 tiles per box: 10 x 12 = 120 tiles; 132 after waste; buy 7 boxes.
How to measure
Measure the finished area, not including baseboard thickness if you will stop under the trim. Tile size is the face size on the carton. Grout gap is the joint width (often 1/8 in). Use 0 for rectified tile laid tight.
FAQ
How many 12x12 tiles do I need for a 10x12 room?
With no grout gap and 10% waste this calculator recommends 132 tiles, which is 7 boxes at 20 tiles per box.
Why do you count tiles along each edge?
Area division can hide leftover strips. Rounding each side up matches how tiles are actually laid.
What waste percent should I use for tile?
10% is typical for a straight layout. Use 15% or 20% for diagonals, herringbone, or many cuts around fixtures.