How to measure a shower for tile
Treat the surround as separate planes, not one “bathroom tile” number. For an alcove, measure the back wall width and height, then each side wall’s depth (into the shower) and height. Multiply each plane in feet for square footage, then add. Optional floor and ceiling use the same length × width rule. Tile size stays in inches; face area is inches × inches ÷ 144.
Example default above: back 40 sq ft + left 24 + right 24 = 88 sq ft walls. At 15% waste with 12″ × 12″ tile that is 101.2 sq ft to order → 102 tiles. Change any field and the working updates.
For a single rectangle (one floor or one wall) use the Tile Calculator. After you know area, the Grout Calculator covers joint material from tile size and joint width.
How niches and openings change the takeoff
A niche is not free tile. The recess adds two side returns, a top, a bottom, and usually a back — all in inches, converted to square feet. If you already counted the niche face as part of the wall rectangle, uncheck “include niche back” so that face is not counted twice. Large untiled openings (glass entry that replaces a tiled wall, a window, a fixture panel you skip) go in the openings field and subtract from gross. Net area never goes below zero.
Waste is a judgment call
The 15% starting point is this site’s labeled wall/shower convention — the same figure used in Wall / shower mode on the generic tile tool. It is not from the TCNA Handbook and not from a manufacturer product data sheet. Niches, benches, curbs, herringbone or diagonal patterns, and large-format porcelain that punishes a bad cut all burn more. See Tile Waste Factor for how those conventions are framed, and Methodology for how this site treats conventions versus sourced yields.
Exclusions
This calculator does not:
- Size or slope a shower pan, liner, or drain
- Count a bench, curb, half-wall, or seat as a dedicated surface type
- Layout patterns, schluter profiles, or trim pieces
- Estimate thinset, waterproofing, or grout pounds (use the grout tool for joints)
- Invent carton coverage — enter sq ft per box from your packaging