Flooring and Tile Calculator
How much flooring or how many tiles, including waste.
Good to know. Add 10% for cuts, 15% for diagonal patterns. A spare tile is cheaper than a missing one.
How it works
In plain words
Multiply length by width for the floor area, then add the waste percentage for cuts and breakages. Divide by the area of one tile and round up to get the number of tiles.
The formula
area = length × width to buy = area × (1 + waste ÷ 100) tiles = roundUp(to buy ÷ tile area)
Worked example
A 4 × 3.5 m floor is 14 m². With 10% waste, buy 15.4 m². Each 60 × 30 cm tile covers 0.18 m², so you need 86 tiles.
Sources
No outside data or rates: this is plain arithmetic.
6 automated tests check its answers on every change.
About the flooring and tile calculator
Whether you are laying tiles, laminate, vinyl planks or carpet, the starting point is the floor area: length times width. For L-shaped rooms, split the floor into rectangles, work each one out, and add them together.
You always need more than the exact area, because tiles and planks have to be cut to fit around edges, doorways and pipes, and a few will break or turn out to be flawed. That extra is the waste allowance. 10% is the usual figure for a simple, straight layout. For diagonal, herringbone or chevron patterns, or rooms with lots of corners, allow 15% or more. For large-format tiles, where every cut wastes a lot, lean higher too.
Flooring is usually sold by the box, and each box states how much area it covers or how many pieces it contains. Enter the pieces per box to see how many boxes to buy, and always round up.
Keep a few spare tiles or planks after the job. If one gets damaged in future, finding an exact match from a different production batch can be difficult. Buying everything from the same batch at the start also avoids slight colour differences.
Questions people ask
How many tiles do I need?
Divide the floor area (plus waste) by the area of one tile, and round up. 15.4 m² with 60 × 30 cm tiles (0.18 m² each) needs 86 tiles.
How much extra flooring should I buy?
About 10% for straight layouts and 15% or more for diagonal or herringbone patterns.
Do I need to include the area under kitchen units?
Usually not, unless the flooring must go under them. Many fitters stop at the kickboards. Check what your flooring manufacturer recommends.