Tile Coverage Calculator – How Many Tiles Do You Need?

How to Calculate Tile Coverage

Accurate tile quantity estimation prevents costly project delays and unnecessary waste. Whether you are tiling a bathroom floor, kitchen splashback, or outdoor patio, our tile coverage calculator tells you exactly how many tiles you need based on the area to be covered and your chosen tile size. It also accounts for wastage from cuts, breakage, and pattern matching.

Enter the total area in square metres (or the length and width of the space), the tile dimensions, and the grout joint width. The calculator returns the number of tiles required, the total coverage area, and the number of boxes to purchase based on standard pack sizes.

Measuring the Area to Be Tiled

For floors, measure the room length and width at the widest points. For walls, measure the height and width of each wall to be tiled. If tiling a splashback, measure just the area between the benchtop and overhead cabinets. Add all individual areas together for the total.

Irregular rooms, niches, and alcoves should be broken into separate rectangular sections, calculated individually, and then combined. Do not subtract small areas for fixtures like power outlets — you will still need tiles cut around these, and the offcuts are usually unusable for other positions.

Allowing for Waste

No tiling job uses exactly the calculated number of tiles. Cuts along walls, around fixtures, and at doorways always produce some waste. As a general rule, add 10% to your calculated quantity for a standard grid layout. For diagonal or herringbone patterns, add 15%. For complex shapes or large-format tiles in small spaces, allow 15–20%.

It is also wise to keep a few spare tiles after your project is complete. If a tile cracks or chips in the future, having a matching replacement from the same batch ensures consistent colour and finish. Tile batches can vary in shade, so purchasing all your tiles in one order is strongly recommended. Our calculator includes a configurable wastage percentage so you can get the right number first time.