Tile quantity calculator: from floor area to boxes
Quantities · 7 min read · updated 17 September 2026 · Written by Tilelico
There are two answers to “how many tiles do I need?”: a quick area estimate and a grid-based count suitable for ordering. They rarely produce the same number, and only one of them survives contact with the room.
Free calculator
How many tiles do I need?
Area-based estimate: 10 % is common for a straight lay, 15 % for diagonal or awkward rooms. It ignores how cuts actually fall, which only a layout plan shows.
Get the exact count with cuts: draw my room →Start with the area estimate
Divide the surface to cover by the face area of one tile. A 600 × 600 tile covers 0.36 m², so 20 m² suggests around 56 tiles.
Treat this as a theoretical minimum, not an order. It assumes every offcut can be reused somewhere else, that nothing breaks, and that tiles are sold individually — three assumptions that are all false on a real job.
Continue with: Tile layout planning: the complete method before installation →
Count tiles on the grid
Generate the actual layout and count every full tile plus every source tile broken into for a cut. A 5 cm strip along a wall consumes an entire tile even though 55 cm of it ends up in the skip.
This is the number that matters, because it is the number of tiles that will leave the supplier on a pallet. The area estimate describes the floor; the grid count describes the purchase.
The gap between the two figures is not error, it is information: a wide gap means the grid is producing many cuts, and it is usually worth moving the origin before ordering.
Continue with: Tile waste calculation: cuts, reuse and ordering allowance →
Allow for reusable offcuts
A straight strip cut from one side of the room can sometimes serve the opposite side, provided the two cuts are the same width and the pattern permits it.
L-shaped and irregular remnants are far less predictable. Treat reuse as an optimisation that may reduce the total, never as a saving you can count on before the tiles arrive.
Continue with: Tile adhesive calculator: how much adhesive per m²? →
Account for the pattern
A straight layout produces cuts on the perimeter only. A diagonal layout cuts almost every boundary tile, and a herringbone pattern produces angled offcuts that rarely pair up.
This is why a single fixed percentage cannot cover every project: the pattern, not the room, decides how much material the boundary consumes.
| Pattern | Where the cuts fall | Typical reuse |
|---|---|---|
| Straight | Perimeter only, often two sides | Good — strips frequently pair up |
| Half offset | Perimeter, alternating widths per row | Fair — two strip widths to match |
| Diagonal 45° | Every boundary tile, triangular pieces | Poor — corners rarely reusable |
| Herringbone | Perimeter plus angled starts | Poor — orientation-dependent |
Convert the total into boxes
Add the chosen job-site allowance, divide by the pieces per box or the coverage per box, and always round up. A box opened for one tile is a box bought.
Keep a few matching tiles once the job is finished. Batch colours drift between production runs, and a repair made with a later batch is visible for the life of the floor.
The figures quoted here describe common practice, not imposed rules. The data sheet for your covering and for your installation products always takes precedence, and measurements taken on site are the reference.
Frequently asked questions
Should I always add ten percent?
No single percentage fits every project. Straight layouts in regular rooms generally need less than diagonal patterns or highly irregular spaces, and the figure should come from the calculated cuts rather than from habit.
Why does the grid count exceed the area calculation?
Because cut tiles are purchased whole and many remnants cannot be reused elsewhere. The difference grows with tile size: a large format wastes more material per cut.
Do I order by tile or by box?
By box. Calculate in tiles, then round up to whole boxes at the very last step, using the pieces per box printed on the packaging.
Read next
Technical references
This guide describes common installation practices. It does not replace applicable technical documents, manufacturer instructions or measurements taken on site.