Calculate how many tiles you need for floors, walls, and splashbacks. Enter area dimensions and tile size to get exact quantities with waste allowance.
Calculate floor, wall, and sloped surface areas from dimensions
Straight lay: 10% waste. Diagonal (45°): 15% waste. Herringbone/chevron: 15-20% waste. Complex patterns with multiple tile sizes: 20-25%. Always order extra — dye-lots change between production runs.
Common sizes: 300×300mm = 11.1 tiles/m², 300×600mm = 5.6 tiles/m², 600×600mm = 2.8 tiles/m², 150×150mm = 44.4 tiles/m². Larger tiles mean fewer cuts but more waste per cut.
Grout needed depends on tile size, joint width, and tile depth. For 300×300mm tiles with 3mm joints: about 0.5 kg/m². For 600×600mm with 5mm joints: about 0.4 kg/m². A 5kg bag covers about 10 m².
Always order 10-15% more than calculated. Keep 1-2 boxes for future repairs. Tile batches vary in colour and calibration — mixing boxes during installation gives a more uniform appearance.
A = length × width - openings
tiles_per_m² = 1 / (tile_w × tile_h)
tiles = ceil(A × (1 + waste%) × tiles_per_m²)
cost = (tiles / tiles_per_box) × price_per_box
For wet rooms, waterproof tanking must be installed before tiling by a specialist. For heavy stone tiles on walls, verify the substrate can support the weight (max 32 kg/m² for plaster, 50 kg/m² for tile backer board).
Tiles per m² = 1/(0.6×0.6) = 2.78. With 10% waste: 20 × 1.10 × 2.78 = 61.2 → 62 tiles. If sold in boxes of 4: buy 16 boxes (64 tiles).
For 300×300mm tiles with 3mm joints: 0.5 kg/m². For a 20 m² floor: 10 kg = 2 bags of 5kg. For larger tiles or wider joints, use an online grout calculator for precision.
Use 15% waste for diagonal (45°) laying. For herringbone or complex patterns, use 15-20%. The more cuts at the perimeter, the more waste you generate.
Yes, most floor tiles can be used on walls, but wall tiles cannot be used on floors — they're not rated for foot traffic. Check the PEI rating: PEI 3+ for floors, PEI 1-2 for walls only.