Tile Calculator — Tiles, Adhesive & Grout Estimator
Calculate exactly how many tiles you need for any floor or wall, including adhesive and grout. Enter your room dimensions, choose a tile size and layout pattern, and get a complete material list with waste factor included.
How the tile calculator works
- 1Calculate the total area to tile (length × width in m²)
- 2Divide area by single tile area to get base tile count
- 3Apply waste factor: straight lay 10%, diagonal 17%, herringbone 15%
- 4Adhesive: multiply net area by kg/m² rate — 3.5 kg for tiles ≤200 mm, 4.5 kg up to 400 mm, 5.5 kg for large format
- 5Grout: calculated from tile perimeter, joint width, tile thickness and grout density (1.7 kg/dm³)
- 6Round up tiles to nearest whole number; round adhesive and grout up to nearest pack
Worked example
Bathroom floor: 2.4 m × 3.2 m = 7.68 m². Tile size 300×300 mm, 10 mm thick, straight lay (10% waste).
You need 94 tiles (0.09 m² each), 38 kg adhesive (4.5 kg/m²), and ~2.9 kg grout at a 3 mm joint width.
Frequently asked questions
How much extra tile should I buy for waste?
For a straight lay add 10%, diagonal or herringbone patterns 15–17%. Always buy at least one spare box — tiles can crack during installation and dye lots change.
How much adhesive do I need per m²?
Standard tiles (≤200 mm): 3.5 kg/m². Medium format (200–400 mm): 4.5 kg/m². Large format (>400 mm): 5.5 kg/m² — large tiles also require back-buttering.
How do I calculate grout for tiles?
Grout quantity depends on tile size, joint width and tile thickness. Use the formula: ((L+B)÷(L×B)) × joint width × tile thickness × 1.7. Our calculator does this automatically.
How many tiles do I need for a 10 m² bathroom?
For 300×300 mm tiles with 10% waste you need approximately 124 tiles. For 600×600 mm tiles you need approximately 31. Use the calculator above for your exact tile size.
What tile size is best for a small bathroom?
Larger tiles (≥400 mm) create fewer grout lines and make small spaces feel bigger. However, large-format tiles require a very flat substrate and experienced installation.