Tile Calculator
Enter your room and tile dimensions — the tile count and grout estimate update as you type, and the link in your address bar always reflects your numbers.
How this calculator works
The room area is length times width. Each tile's coverage comes from its printed dimensions in inches, converted to square feet (tile length × tile width ÷ 144). Dividing the waste-adjusted room area by the coverage of one tile gives the tile count, rounded up since tiles are bought whole. The grout figure is a separate, clearly-approximate planning number — about 1 lb of grout per 10 sqft of tiled area for standard 1/8 in joints — useful for a first shopping trip, not for a final material order.
Worked example
A room 8 ft by 6 ft has an area of 8 × 6 = 48 sqft. Using 12×12 in tiles, each tile covers (12 × 12) ÷ 144 = 1 sqft. With a 10% waste factor, the area to cover is 48 × 1.10 = 52.8 sqft, so tiles needed = 52.8 ÷ 1 = 52.8, rounded up to 53 tiles. The grout estimate is 48 ÷ 10 = 4.8, rounded up to 5 lbs — again, a rough planning figure, not a precise spec.
Frequently asked questions
Why does tile size change the count so much?
Bigger tiles cover more area each, so it takes far fewer of them to fill the same room — and the effect compounds fast because area scales with the square of the tile's side. On a 48 sqft floor with 10% waste, 12×12 in tiles (1 sqft each) need 53 tiles, but 6×6 in tiles (0.25 sqft each, a quarter the area) need 212 tiles — exactly 4× as many, because each tile covers a quarter of the area. Bigger tiles also mean fewer grout lines, which is a separate reason installers often prefer them for large open rooms.
Is the grout estimate accurate?
No — be clear-eyed about this one. It's a rough planning figure (about 1 lb of grout per 10 sqft for standard 1/8 in joints), not a precise spec. Real grout usage depends heavily on tile size (more tiles means more joints means more grout), joint width, grout depth, and tile thickness. Before buying, check the coverage chart printed on the specific grout bag you're using — it accounts for your exact joint width and will be far more accurate than any general rule of thumb.
Should I buy extra tiles in case I need repairs later?
It's common practice among installers and a good idea — keeping a few spare tiles from the same production batch means a future crack or chip can be replaced with a matching tile, since tile lines and dye lots often change or get discontinued over time. This calculator doesn't add that buffer automatically since it's a personal choice rather than a project requirement, but it's worth factoring in when you place your order.
Does this work for wall tile too?
Yes — the math is identical for floor and wall tile. Just measure the wall's height and width (or the area you're tiling) instead of the floor's length and width, and enter your tile size as usual. Everything else — waste factor, tile count, and the grout estimate — works exactly the same way.