Construction

Tile Calculator

Calculate exactly how many tiles you need for any floor or wall project. Accounts for room area, tile size, and a customizable wastage percentage.

10% is standard; use 15–20% for diagonal or complex patterns

Enter room and tile dimensions to calculate the number of tiles needed.

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Tile Count Formula

The number of tiles is the room area divided by the area of one tile, rounded up, then multiplied by the wastage factor.

Tile area (ft²) = (L ÷ 12) × (W ÷ 12)

Tiles = ⌈ Room ft² ÷ Tile ft² ⌉ × (1 + waste%)

Example: 120 ft² room with 12×12 tiles → ⌈120 ÷ 1⌉ × 1.10 = 132 tiles

Tile Buying Tips

Tiles are typically sold by the box, so check how many tiles come in a box and calculate how many boxes you need. Always buy from the same production lot (same lot number on the box) to ensure color and pattern consistency across the entire installation.

Keep leftover tiles after installation. Tiles get discontinued, color lots change, and future repairs will need an exact match. Storing 5–10 spare tiles per room is a common recommendation from professional tile installers.

Frequently asked questions

How do I calculate how many tiles I need?
Divide the room area by the area of one tile, then add a wastage allowance. For example, a 120 sq ft room tiled with 12×12 inch tiles (1 sq ft each) needs 120 tiles before waste. Adding 10% gives 132 tiles. This calculator handles the math automatically — just enter the room and tile dimensions.
How much tile wastage should I allow?
A 10% wastage allowance is standard for simple rectangular rooms with straight-lay tile patterns. Use 15–20% for diagonal (45-degree) patterns, rooms with irregular shapes, or large format tiles (24 inches or bigger). Always buy a few extra tiles beyond your calculation and store them for future repairs, since color lots change over time.
What is the most common tile size?
The 12×12 inch tile has historically been the most popular floor tile size in the US. Modern trends favor larger formats: 24×24 inch and 18×18 inch tiles are now very common for open floor plans. Small mosaic tiles (1×1 inch or 2×2 inch) are popular for shower floors and backsplashes. Enter any custom size in the calculator.
Should I include door and window areas in my tile calculation?
For floor tiles, no — you only tile the floor area, not door openings. For wall tiles, you should measure the full wall area and then subtract window and door openings. It is generally better to calculate without subtracting and use the surplus as extra wastage, especially if the room has many windows or irregular walls.
How do I convert tile size to square feet?
Divide the tile dimensions in inches by 12 to get feet, then multiply to find the area. A 12×24 inch tile is 1 ft × 2 ft = 2 sq ft per tile. A 16×16 inch tile is 1.33 ft × 1.33 ft = 1.78 sq ft per tile. This calculator handles the inch-to-foot conversion automatically.

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