RoomKitHow it works
This calculator estimates floor tiles from area, using the nominal tile length and width. Add a waste allowance for cuts, breakage and spares, then round pieces up before rounding to whole boxes. It does not calculate individual cuts, grout gaps, joints, tile orientation or whether offcuts can be reused. A diagonal pattern, irregular room or small border pieces may need a different allowance. Check the final layout and the manufacturer’s box coverage before ordering.
Formula
Required tile area = floor area × (1 + waste/100). Tiles = round up (required area ÷ tile area). Boxes = round up (tiles ÷ tiles per box).
Example
A 4 × 3 m floor has 12 m². At 10% waste, plan for 13.2 m². With 30 × 30 cm tiles, the area estimate needs 147 tiles. At ten tiles per box, buy 15 boxes or 150 tiles. At 20 per box the estimated tile cost is 300. Adhesive, grout, delivery and installation are not included.
Assumptions and limitations
Use the coverage and pack size printed on your product label. Output estimates, not a cutting or installation plan. Materials only. Labor, delivery, tax, primer, adhesive and underlay are excluded.
Sources and assumptions
BEHR · Paint · The Home Depot · Material calculators
Frequently asked questions
Are my measurements uploaded?
No. Your room measurements, product settings, units and currency are stored in this browser. Clear this site’s data to remove them.
Does changing units change the room?
No. Dimensions stay in metres internally. Metric and imperial views convert lengths, areas, litres and US gallons without changing the stored room.
Are the coverage and waste defaults guaranteed?
No. Defaults are examples. Use your product label and adjust for the surface, layout, cuts and installation instructions.