Tile calculator
Enter the room and the tile size to get the tile count, boxes to buy and area covered — with wastage you control instead of a hidden markup.
| Breakdown | Value |
|---|
Estimate. The method and sources are on this page — check them against your own case before you act.
How it is calculated
Tile estimating is floor area divided by tile area, then rounded up twice — once to whole tiles and once to whole boxes. The calculator does both, because you cannot buy a fraction of a box.
Tiles = floor area (m²) ÷ tile area (m²) × (1 + wastage) · Boxes = tiles ÷ tiles per box
Measure the floor, not the walls
Length × width in feet gives square feet; multiply by 0.092903 for square metres. Measure each room separately if the tiles differ, then add the rooms.
Convert the tile size to area
A 600 × 600 mm tile is 0.36 m², a 300 × 300 mm tile is 0.09 m². Tiles are sold by box, and the carton states how many pieces and how much area it covers.
Round up, then add wastage
Divide the floor area by the tile area and round up. Add 5% for straight laying or 10% for diagonal patterns, then round up again to full boxes.
Tile sizes and coverage
| Tile size | Area per tile | Tiles per 100 sq ft | Common use |
|---|---|---|---|
| 300 × 300 mm | 0.09 m² | 103 | Bathroom and utility floors |
| 300 × 450 mm | 0.135 m² | 69 | Bathroom walls |
| 450 × 450 mm | 0.2025 m² | 46 | Older living rooms and kitchens |
| 600 × 600 mm | 0.36 m² | 26 | Living rooms and bedrooms |
| 800 × 800 mm | 0.64 m² | 15 | Large-format floors |
| 600 × 1200 mm | 0.72 m² | 13 | Large-format floors |
| 1000 × 1000 mm | 1.0 m² | 10 | Premium large-format floors |
What most pages get wrong
You buy boxes, so the answer is rounded to boxes
A 600 × 600 tile box usually holds 4 pieces, about 1.44 m². Rounding tiles without rounding boxes leaves you one box short at the end of the room.
Straight laying wastes less than diagonal
5% is normal for a rectangular room laid straight. Diagonal or herringbone patterns cut every edge tile, so plan on 10%.
Bigger tiles mean fewer joints, more waste
A 600 × 1200 mm tile covers twice the area of a 600 × 600 tile, but cut-offs at walls are larger. Ask the tiler about the laying pattern before ordering.
Keep one box for later repairs
Dye lots change. Keeping one unopened box from the same batch makes a future repair invisible — add it to your order if the budget allows.
Frequently asked questions
How many 600 × 600 tiles do I need for a 12 × 10 ft room?+
How much area does one box of tiles cover?+
Should I use 5% or 10% wastage?+
Can I use this calculator for wall tiles?+
What if my room is not a rectangle?+
Why is the area ordered larger than my floor area?+
Sources, dates and a changelog.
Every number this calculator uses is either an input you control or a value from the sources below. The formula is compiled and tested at build time, so the page cannot ship with a broken calculation.
Sources
This page
- Last verified: 29 October 2026
- Next review: 29 April 2027
- Vertical: Construction & Real Estate
- Build tests: 4 passed
- Changelog: 1 entry
How we handle errors
- Spotted a mistake? Report it — we correct and log it.
- Corrections appear in the changelog below.
- Read the methodology and the disclaimer.