How to use the Tile and Flooring Quantity Calculator
- 1. Enter the roomRoom length and width in metres or feet, and any area that will not be tiled.
- 2. Enter the tileTile size in mm, joint gap, wastage and tiles per box.
- 3. Get the countFloor tiles, skirting tiles, boxes and the mortar bed materials if needed.
How tiles are counted
Tiles = area to tile ÷ area of one tile with its joint, rounded up, then add wastage for cutting and breakage (often 5–10% for straight laying, more for diagonal patterns). The layout method counts rows × columns, rounding each up, which is closer to reality in small rooms where every edge tile is cut.
Skirting length = room perimeter − door widths. Each tile is cut into strips of the skirting height, so a 600 mm tile gives six 100 mm strips. A cement mortar bed volume is area × thickness; multiply by the dry volume factor (commonly 1.27) and split by the mix ratio to get cement and sand.
Worked example and site tips
Room 4.2 × 3.6 m with 600 × 600 mm tiles and 2 mm joints: one tile covers 0.602 × 0.602 = 0.3624 m², so 15.12/0.3624 = 41.7 → 42 tiles. With 10% wastage: 47 tiles. Skirting 100 mm high: (15.6 − 0.9)/0.602 = 25 strips → 5 tiles.
- Buy all tiles with the same shade and batch code.
- Keep a few spare tiles for later repairs.
- Large tiles (800 mm and up) waste more in small rooms. Use the layout count.
Frequently asked questions
How many tiles do I need for 100 sq ft?
With 2 × 2 ft (600 mm) tiles, one tile covers about 4 ft², so about 25 tiles plus 5–10% wastage. Enter your exact size for a precise count.
How much wastage should I add?
About 5–10% for straight laying in a regular room, and 10–15% for diagonal laying or rooms with many corners.
Why are area and layout counts different?
The area method assumes cut pieces are reused. The layout method counts every row and column, so it is safer in small rooms.
Is this calculator free?
Yes. You fill a short form once to see your result, and other Uncodemy tools then open without the form. Everything is calculated in your browser and nothing you type is uploaded.