How to use this calculator
- Measure area. Length × width of the surface in feet (or meters).
- Tile size. Enter tile length and width in inches (e.g. 12×24).
- Set waste. Default is 10%. Use 15% for diagonal layouts or complex cuts.
- Box count. Enter tiles-per-box from the spec sheet — defaults to 10.
Formula
Tiles = ceil(area / tile_area × (1 + waste%))
Worked example
A 10 × 12 ft floor (120 ft²) with 12×12 in tiles needs 132 tiles (120 × 1.10). At 10 tiles per box, that's 14 boxes.
Common project sizes
Quick reference for the most common tile calculator use cases. Use these as a sanity check on your calculator inputs.
| Project | Dimensions | Result |
|---|---|---|
| Bathroom floor (5×8 ft) | 40 ft² | 44 tiles (12×12) · 5 boxes |
| Kitchen backsplash (15 ft run, 18" tall) | 22 ft² | 88 tiles (6×6) · 9 boxes |
| Shower walls (3 walls, 6 ft tall, 4 ft wide each) | 72 ft² | 79 tiles (12×12) · 8 boxes |
| Living room floor (15×20 ft) | 300 ft² | 198 tiles (24×24) · 50 boxes |
2026 cost reference
Typical retail price range in the United States for tile. Local pricing varies by region, supplier, and grade — confirm with two or three quotes before ordering.
Per ft²
$0.80 – $15+
Builder-grade ceramic starts around $0.80–$2/ft². Mid-range porcelain is $3–$7/ft². Designer or natural stone runs $10–$15+/ft². Add $4–$10/ft² for installation if you hire it out.
By the numbers — regional pricing
Snapshot of current US pricing for square foot (porcelain field tile, builder grade installed), broken down by Census region. Source: National installer survey + big-box retail tile pricing; designer and natural stone excluded.. Data as of April 2026; we refresh quarterly.
| Region | Low | High | Note |
|---|---|---|---|
| Northeast | $9 | $18 | — |
| Midwest | $7 | $15 | — |
| South | $6 | $14 | — |
| West | $10 | $22 | Bay Area + LA installer labor at $14–$22/ft² installed. |
How we calculate this
Assumptions baked in
Tiles needed = ceil((Area × (1 + waste%)) / tile_area_in_ft²). Default waste is 10% for straight (grid) layouts. For diagonal, herringbone, or pattern layouts, use 15%. For shower floors with multiple drains and cuts, 20%. Box-count = ceil(tiles ÷ tiles_per_box). Thinset usage assumes a ¼" × ¼" × ¼" square-notch trowel for tiles up to 12×12; larger tiles need ½" notches and consume thinset faster (75 ft² per 50 lb bag).
Accuracy and margin of error
Tile count is exact for the input dimensions. Box rounding can push the order significantly over for small jobs — for a 25 ft² backsplash with 4×4 tiles, 30 tiles needed but the box may hold 50, forcing a $40–$60 overshoot. Order from the same dye lot to avoid shade variation; save 5–10 leftover tiles for future repairs (manufacturers discontinue lines on a 3–5 year cycle).
Edge cases this calculator does not handle
Large-format tile (24" and up) requires a flat substrate (typically 1/8" in 10 ft) and a back-buttering technique with mortar applied to both substrate and tile back. Glass mosaic uses white thinset (gray bleeds through) and a non-sanded grout. For wet areas (showers, tub surrounds), the substrate must be waterproofed with a membrane (Schluter Kerdi, RedGard, or Wedi) — the calculator does not factor this material; budget $1.50–$3.50/ft² for waterproofing.
Cited sources for this page
The figures and rules above are anchored to the following normative references. We link the underlying claim to its standard — not as generic SEO trust signals, but so you can audit any number on this page against a primary source.
Tile installation methods including waste allowance, substrate flatness, and waterproofing requirements are documented in the TCNA Handbook for Ceramic, Glass, and Stone Tile Installation.
Source: TCNA Handbook for Ceramic, Glass, and Stone Tile Installation (2026 edition)
Substrate flatness requirement of 1/8" in 10 feet for large-format tile is published in ANSI A108.5 and TCNA F101.
Source: ANSI A108.5 Installation of Ceramic Tile with Dry-Set or Latex-Modified Portland Cement Mortar
Tips for accurate results
- Always order from the same dye lot — colors vary between production runs.
- Add 15% waste for diagonal patterns, herringbone, or unusual layouts.
- Save 5–10 leftover tiles for future repairs — they may be discontinued later.
- Heavy floor tile (12+ mm) needs a larger trowel and more thinset.
Common mistakes to avoid
- Buying exactly the calculated count with no waste — every project needs cuts and ends up with broken tiles.
- Mixing tile from different dye lots — even the same SKU varies between production runs.
- Forgetting underlayment cost (cement backer board adds about $1.50/ft²).
- Skipping the spacer plan — grout-line width changes how many tiles fit per row, which can shift the layout off-center.
When to consult a pro
DIY tile is reasonable for a flat, square floor under 100 ft² if you own (or rent) a wet saw. Get help with mosaics, large-format tile (18+ inches), shower pans, mud-bed installations, or any tile over radiant heat — these need waterproofing or movement-joint work that, done wrong, leads to leaks and cracked grout within a year.