How many tiles you need depends on your room size, tile dimensions, and layout pattern. A simple grid layout wastes less tile than a herringbone pattern, and that difference can mean an extra box or two. Here's how to calculate it right.
How Many Tiles Do You Need?
Divide your room area by the area of a single tile, then multiply by your waste factor. For a **12x10 foot** room (**120 sq ft**) with **12x24 inch tiles** covering **2 sq ft each**, you need at least 60 tiles. With the standard **10% waste factor**, that becomes **66 tiles** -- or about **7 boxes** at 10 tiles per box.
Waste Factor by Layout Pattern
| Layout Pattern | Waste Factor | Best For |
|---|---|---|
| Standard Grid | 10% | Large rooms, simple installation |
| Brick / Staggered | 10% | Subway tiles, classic look |
| Diagonal | 15% | Small rooms, adding visual space |
| Herringbone | 20% | Feature walls, accent areas |
Herringbone creates the most waste because of the complex angle cuts at every edge. Grid layouts are the most efficient -- you'll cut fewer tiles and have less leftover scrap.
Why Tile Size and Grout Lines Matter
Larger tiles cover more area with fewer grout lines, which means less cutting and lower waste. But a single miscut on a **24x48 inch** tile costs more than a miscut on a **12x12 inch** tile. Grout lines also affect your count -- a **1/8-inch** grout line between 12-inch tiles reduces the tile quantity by about **1-2%** since each tile's effective coverage area expands slightly.
Always order at least one extra box beyond your calculated amount. Store it safely -- if a tile breaks in the future or the product line gets discontinued, you'll be glad you've matching tiles from the same dye lot.
Starting a tiling project?
Use the Tile Calculator to get the exact number of tiles and boxes you need. It supports grid, brick, diagonal, and herringbone layouts with automatic waste factors.