Tiles & paint calculator
A quick tiles calculator for any room, enter the length, width and tile size to get the number of tiles and full boxes to buy, with a built-in wastage allowance.
Switch to paint mode to turn a wall area, the tin's coverage and the number of coats into litres and tins. A planning-level tool for renovations and new builds, computed entirely in your browser.
What are you estimating?
Side of a square tile, e.g. 600 for a 600 × 600 mm tile.
Check the carton: large tiles often pack 2–4 per box.
Extra for cuts, breakage and future repairs: usually 10%.
Tiles needed
43 tiles
Covering 14.00 m² floor (incl. 10% wastage)
Boxes to buy
11
Floor area
14.00 m²
Per tile
0.360 m²
Tiles
43
Boxes
11
| Tiles formula | ceil( floor ÷ tile × (1 + waste) ) |
| Floor area | 4 m × 3.5 m = 14.00 m² |
| Tile area | 600 mm² → 0.360 m² per tile |
| With wastage | × (1 + 10%) = 43 tiles |
| Boxes | ceil( 43 ÷ 4 per box ) = 11 |
A planning-level estimate. Tile counts assume square tiles laid straight with no large feature cuts; diagonal, herringbone or patterned layouts need more. Paint coverage varies with surface porosity, colour change and application, always check the figure printed on the tin and buy a little extra.
From room dimensions to a shopping list
Tiles come down to floor area divided by tile area, padded for wastage and rounded up to whole boxes; paint is wall area times coats divided by the coverage printed on the tin.
Measure the area
For tiles, multiply room length × width in metres. For paint, total the wall or ceiling area and subtract large doors and windows.
Divide by the unit
Tiles: area ÷ one tile's area (a 600 mm tile is 0.36 m²). Paint: area × coats ÷ coverage (m² per litre).
Pad and round up
Add ~10% tile wastage for cuts and breakage, then round up to whole tiles, boxes and paint tins.
Tiles & paint, answered
How do I calculate how many tiles a room needs?+
Work out the floor area (length × width in metres), then divide by the area of one tile. A 600 × 600 mm tile covers 0.36 m², so a 14 m² room needs 14 ÷ 0.36 ≈ 39 tiles before wastage. Add a wastage allowance, usually 10%, for cuts and breakage, then round up to whole tiles and boxes.
How much wastage should I add for tiles?+
A 10% allowance is the common rule of thumb for a straight (grid) layout in a simple rectangular room. Allow more, 12–15%, for diagonal or herringbone patterns, many cuts around fittings, or large-format tiles where a single break is costly. The default here is 10%.
Why does the calculator round up to whole boxes?+
Tiles are sold by the box, not individually, so the boxes figure rounds up: boxes = ceil(tiles ÷ tiles-per-box). Buying full boxes also leaves a few matching spares from the same batch, which is useful for future repairs since later production runs can differ slightly in shade.
How is the amount of paint calculated?+
Litres = wall area × number of coats ÷ coverage. Coverage is the area one litre covers in a single coat, printed on the tin, emulsion is typically about 10–14 m² per litre. For a 40 m² wall at 10 m²/L with two coats: 40 × 2 ÷ 10 = 8 litres.
What paint coverage should I use for Nepal?+
Use the figure on your specific tin, as it varies by brand and product. Common interior emulsions quote roughly 10–14 m² per litre per coat on a smooth, primed wall; rough plaster, fresh putty or a strong colour change reduces coverage and may need an extra coat. The default 10 m²/L is a safe, conservative starting point.
Should I subtract doors and windows?+
For paint, yes, subtract large openings such as doors and picture windows from the wall area for a tighter estimate, though many people leave small windows in as a built-in margin. For floor tiles, measure the actual floor to be covered and rely on the wastage allowance for the rest.
Sources & data note
Tiles = ceil(floor area ÷ tile area × (1 + wastage)); paint litres = wall area × coats ÷ coverage. Tile sizes follow common IS 15622 nominal dimensions and coverage defaults reflect typical emulsion practice. These are indicative planning estimates, confirm the coverage printed on your paint tin and your tiles-per-box, and verify quantities with your supplier before buying.