How Many Tiles Do I Need?

How Many Tiles Do I Need?
Enter your room size and tile dimensions to get exact tile count, boxes to buy, and an optional cost estimate — works for floor tile, wall tile, and backsplash.
⚡ Quick Answer

A 10×12 floor (120 sq ft) using 12×12 inch tiles with 10% waste needs 132 tiles. If each box covers 15 sq ft, buy 9 boxes. Use the calculator below for any tile size.

Project Area


Tile Size


Common sizes: 12×12, 6×24, 24×24, 3×6 subway. Enter in inches.


Grout spacing is for layout reference — tile count uses tile size only.
Optional: Boxes & Cost


Box coverage is printed on the package. Leave price blank to skip cost estimate.

Tiles Needed

tiles (including waste)

Project Area
Waste Factor
Boxes to Buy
Est. Cost

✓ What to Buy


Estimate costs near you

How We Calculated This

Tile Waste Guide
10% — Simple straight layout, rectangular room
15% — Diagonal pattern, L-shaped room, many cuts
20% — Herringbone, complex pattern, lots of obstacles

When in doubt, use 15%. Running short mid-job is costly if your dye lot is sold out.

Tile Size Reference
12×12 in — 1 sq ft per tile, most common floor tile
6×24 in — 1 sq ft per tile (plank format)
24×24 in — 4 sq ft per tile, large format
3×6 in — 0.125 sq ft per tile (subway)
4×4 in — 0.11 sq ft per tile (classic wall tile)

Enter your exact tile dimensions in inches for the most accurate count.

Grout, Dye Lots & Cuts
Grout spacing affects layout planning more than tile count — standard 1/8″ spacing has a negligible effect on material quantity.

Buy from the same dye lot. Tile color varies between production runs. Always buy at least one extra box for repairs.

Dry-lay first — arrange tiles without adhesive to check your pattern and cut placement before committing.

Tiles Needed by Common Room Size
10% waste included · 12×12 and 12×24 inch tiles · Boxes at 15 sq ft/box
Room SizeArea12×12 Tiles12×24 TilesBoxes (15 sq ft)
5 × 840 sq ft44223
8 × 1080 sq ft88446
10 × 10100 sq ft111568
10 × 12120 sq ft132669
12 × 12144 sq ft1598011
12 × 14168 sq ft1859313
15 × 20300 sq ft33016522
Values rounded up. Divide your area (with waste) by your box coverage to get exact boxes for your product.
Frequently Asked Questions
How many tiles do I need for a 10×12 room?
A 10×12 room has 120 square feet. Using 12×12 inch tiles with 10% waste, you need 132 tiles. At 15 sq ft per box, buy 9 boxes. Use the calculator above for your specific tile size and box coverage.

How much extra tile should I buy for waste?
Add 10% for a simple straight layout in a rectangular room. Add 15% for diagonal patterns, L-shaped rooms, or rooms with many doorways and cuts. Add 20% for herringbone or complex patterns. Always round up to the nearest full box.

How do I calculate tile square footage?
Multiply room length by width for your total area. Then divide by the tile area in square feet — tile length in inches × tile width in inches ÷ 144. For a 12×12 tile: 12 × 12 ÷ 144 = 1 sq ft per tile. The calculator does this automatically.

Does grout spacing affect how many tiles I need?
For most residential tile sizes, grout spacing has a very small effect on tile count — standard 1/8″ grout lines on 12×12 tiles add less than 2% to your area. The waste factor covers this difference.

How many boxes of tile should I buy?
Divide your total area including waste by the box coverage printed on the package, then round up. For 120 sq ft + 10% waste = 132 sq ft ÷ 15 sq ft/box = 8.8, rounded up to 9 boxes.

Should I buy extra tile from the same dye lot?
Yes. Always buy at least one extra box from the same dye lot. Tile color varies between production runs and matching tiles from a different run is difficult. Store extras flat in a climate-controlled area.

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