Tile Calculator
How many tiles and boxes you need for a floor, wall, or shower -- from your area, tile size, grout joint, and waste.
Length x width of the floor or wall. Add every surface for a shower.
1/8" (0.125) is common for floors; 1/16" for rectified tile.
10% for straight layouts; 15-20% for diagonal or herringbone patterns.
Printed on the box; varies by product.
Tiles needed (including waste)
108 tiles
Boxes to buy
11 boxes
Rounded up to whole boxes; keep the spares for future repairs from the same dye lot.
Once you know the tile count, the grout calculator uses the same tile size and joint width to tell you how many pounds of grout the job takes.
Keep going
- Tile count and joint width both feed straight into grout volume; the grout calculator uses the same inputs to size how much you'll need. Grout Calculator
Frequently Asked Questions
How many 12x12 tiles do I need for a 10x10 room?
100 square feet of 12x12 tile is 100 tiles before waste, or 110 with the standard 10% allowance. With a 1/8" grout joint each tile covers slightly more than a square foot, so the calculator above lands at 108 -- the joint is why the count is a little under the naive number.
Why does the grout joint change the tile count?
Each joint is space that isn't tile. A 12x12 tile laid with a 1/8" joint takes up 12.125" x 12.125" of floor, so a fixed area needs slightly fewer tiles than the tile size alone suggests. It's a small effect on big tiles and a bigger one on mosaics.
How much waste should I add?
10% is the standard allowance for a straight lay -- it covers cuts at walls, breakage, and a few spares. Diagonal, herringbone, or any pattern with lots of angled cuts wastes more; 15-20% is the usual guidance. Also round up to whole boxes and keep the extras: replacement tile from a later dye lot rarely matches.