Tile Calculator

Use our free tile calculator to work out how many tiles you need for floors, walls or splashbacks. Enter your measurements to calculate the area in square metres (m²), allow for wastage and estimate whole boxes. Switch to the grout calculator to estimate grout quantities using your tile and joint measurements.

Step 1

Enter the areas you want to tile

Use multiple rectangles for separate surfaces or L-shaped areas. Deductions are optional for openings or sections that will not be tiled.

Gross area 0.00 m²
Openings or deductions Optional. Add untiled rectangular openings or sections.

Step 2

Add your tile details

Step 3

Choose a wastage allowance

Wastage allowances are a planning guide. Check the product and installation requirements before ordering.

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Ready to Choose Your Tiles?

Browse our range of tiles, tile adhesives and grout to compare options for your project. Check the final quantities and product details before ordering.

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Tile & Grout Calculator FAQs

Calculate how many tiles you need by multiplying each area’s length by its width in metres, then subtracting any openings that will not be tiled. Add an allowance for cutting and breakages. Divide the required square metres by the coverage per box and round up to whole boxes. For example, a 4 m × 3 m floor with 10% wastage needs 13.2 m² of tiles.

The number of boxes of tiles you need depends on the area including wastage and the square metres covered by each box. Divide the required area by the box coverage, then round up to the next whole box. If you need 13.2 m² and each box covers 1.44 m², you need 10 boxes. Always check the coverage shown on your chosen tile product page.

A 10% tile wastage allowance is a useful starting point for simple, straight layouts with relatively few cuts. Diagonal or herringbone patterns, irregular rooms and complex edges may need 15% or more. The calculator lets you change the allowance to suit your job. For tricky layouts, ask your tiler to confirm the quantity before ordering.

Calculate how much grout you need using the tiled area, tile dimensions, grout joint width, effective joint depth and the grout product’s density or coverage guidance. Smaller tiles and wider or deeper joints generally need more grout. Our grout calculator provides an estimate in kilograms, not a guaranteed pack quantity. Check the selected grout manufacturer’s instructions before purchasing.

You can calculate tiles for several rooms or walls by adding each area to the calculator, then deducting openings that will not be tiled. The tool combines the net areas before applying your chosen wastage allowance. Measure each separate section carefully, and avoid entering overlapping areas twice. The final estimate is most useful when the same tile and box coverage apply across those areas.

Use your tile calculator results on Ross’s product pages by entering either the measured area with the 10% wastage option selected, or the area already including wastage with that option switched off. Never add wastage twice. If you used a custom allowance, enter the waste-adjusted area and leave the product-page checkbox unticked. The product page calculates the final box quantity and price for that tile.