π« Tile Calculator
Find out how many tiles and boxes you need for your project.
Tiles Needed (incl. waste)
How to Use This Calculator
Enter the area length and width in feet, then enter your tile dimensions in inches. If you know how many tiles come per box, add that number and the calculator will tell you exactly how many boxes to buy. Always include a waste factor of at least 10 percent for straight layouts and 15 percent for diagonal or herringbone patterns.
Measure the floor or wall area in feet. For L-shaped rooms, split into two rectangles, calculate each, and add them together.
Enter the tile length and width in inches. Check the box label for the actual size, which may differ slightly from the nominal size. A "12x12" tile is often 11.75 inches.
Set the waste percentage. Use 10% for simple rectangular rooms. Use 15% for rooms with lots of corners or diagonal tile layouts.
Enter tiles per box from your specific product. This is printed on the box or tile display label. It varies widely by tile size and brand.
Tile Calculation Formula
For a 12x12 inch tile, one tile covers exactly 1 square foot. A 4x8 inch subway tile covers 0.22 square feet, so you need about 4.5 tiles per square foot. Always round up to the next full box when purchasing.
Example Projects
Tips for Your Project
Always buy tiles from the same dye lot. Tile manufacturers batch-produce tiles, and color can vary noticeably between batches. Order everything at once, even if your estimate says you need exactly 4 boxes. Buy 5. Leftover tile is cheap insurance against a cracked or chipped tile two years from now when the batch is discontinued. Store the extras in a dry area, clearly labeled with the product number.
For shower and bathroom floors, plan your tile layout before you cut anything. Start from the center of the room and work outward so cut tiles at the walls are equal size on opposite sides. Cuts smaller than half a tile look bad and are harder to set properly. A quick dry-lay of a few rows before you mix thin-set will save you a lot of frustration.
Frequently Asked Questions
How do I calculate the number of tiles needed?
Divide the total area by the area of one tile. Add 10β15% for cuts and waste. Round up to the nearest whole box.
What waste percentage should I use?
Simple rectangular rooms: 10%. Rooms with lots of cuts (L-shapes, diagonal patterns): 15β20%. Very complex layouts: up to 25%.
How much extra tile should I buy?
Always buy 10β15% extra and keep some for future repairs. Tile batches vary slightly in color, so matching later can be difficult.
What size grout joint should I use?
Small tiles (up to 4"): 1/16" joints. Medium tiles (4β12"): 1/8β3/16". Large tiles (12"+): 3/16β1/4".
Can I tile over existing tiles?
In some cases yes, but it adds height and weight. Check floor load capacity and threshold height before tiling over existing tile.