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Tile Calculator

Calculate tiles needed for floors, walls, or splashbacks in your NZ home. Includes wastage allowance and grout coverage.

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Disclaimer

This calculator provides estimates for general information purposes only. Results are based on standard formulas and may not reflect your individual circumstances. Always consult a qualified professional for advice specific to your situation.

Frequently Asked Questions

How many tiles do I need for a bathroom?
For a typical NZ bathroom of 5–7 m² (3m × 2m floor), you will need around 70–80 standard 300×300mm tiles (including wastage), or about 16–20 large-format 600×600mm tiles. For walls, calculate the wall area separately (length × height) and subtract the doors and windows. Always add 10–15% wastage — more for diagonal layouts or herringbone patterns. Source: Tile Warehouse NZ.
How much wastage should I allow for tiles?
Standard advice is 10% wastage for straight (square) tile layouts, 15% for diagonal layouts, and 20% for complex patterns like herringbone or chevron. Add an extra 5% if tiles are large format (600×1200mm or bigger), as cuts produce larger waste pieces. Always buy from the same dye lot — ordering more tiles later may give a slightly different colour. Source: NZ tile retailers.
How much does tile installation cost in NZ?
Tile installation in NZ costs roughly $40–$80 per square metre for standard ceramic floor tiles, $60–$100 per m² for wall tiles, and $90–$150 per m² for large-format porcelain or natural stone. Add for substrate prep, waterproofing (essential in wet areas, ~$30–$50/m²), and grout sealing. A typical 7 m² bathroom retile costs $1,200–$2,500 for labour plus $300–$1,500 for tiles depending on quality. Source: NZ tradesman quotes 2026.

A tile calculator works out the number of tiles you need for a floor, wall, or splashback project. It accounts for the area being tiled, the size of each tile, plus a wastage allowance (usually 10%) for cuts and breakages.

How this calculator works

Enter the room dimensions (length × width) or the total area, the tile size (e.g. 300×300mm, 600×600mm), and your wastage percentage. The calculator divides the total area by the tile area, adds wastage, and rounds up.

Common NZ Tile Sizes & Coverage

300×300mm (small)~11 tiles per m²
450×450mm (medium)~5 tiles per m²
600×600mm (standard)~3 tiles per m²
600×1200mm (large format)~1.4 tiles per m²
Recommended wastage10% (15% for diagonals/herringbone)

Worked Examples

Bathroom floor 3m × 2.5m, using 600×600mm tiles

~22 tiles needed (incl 10% wastage)

  1. Area: 3 × 2.5 = 7.5 m²
  2. Tile area: 0.6 × 0.6 = 0.36 m²
  3. Tiles needed: 7.5 / 0.36 = 20.8
  4. Add 10% wastage: 22.9 → round up to 23 tiles

Built and maintained by Konstantin Iakovlev. Data sourced from the IRD and official New Zealand government sources.

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