Flooring & tile calculator
Room size to packs on the trolley: area in m², a waste allowance that matches how you lay it, and the pack count rounded the way the shop rounds it.
Opens the editor with this room already drawn — walls, dimensions and the area label. Free, no sign up.
The formula
area × (1 + waste%) ÷ pack coverage, rounded up to whole packs.
Worked through for the defaults: a 4.2 × 3.6 m room is 15.1 m² of floor.
A straight lay adds 5% for offcuts — 15.9 m² to buy. In 2.22 m² packs
that is 15.9 ÷ 2.22 = 7.15, which rounds up to
8 packs (17.8 m² bought).
Non-rectangular rooms are the same formula with a different first term: an L-shape is the overall rectangle minus its cut-out corner, and a T, U or other odd shape is the sum of the rectangles you split it into (the Advanced section handles both, and draws the shape as you type). The waste percentage covers offcuts at walls and obstacles, boards damaged in handling and the pattern's own geometry. It does not cover measuring the room wrong — which is the most expensive mistake of the three, and the one a measured floor plan eliminates.
Common questions
Related: the paint calculator for the same room's walls, and the room sizes & clearances cheat sheet for whether the room itself is the right size.
How much waste should I allow for flooring?
It depends on the laying pattern, not the material. A straight lay parallel to the walls wastes about 5% to offcuts; laying diagonally or matching a tile offset takes about 10%; herringbone and other patterns that cut every edge board at an angle take 15% or more. Small or irregular rooms sit at the top of each range because each obstacle adds cuts.
How do I measure an L-shaped or irregular room?
Open the "Advanced" section under the room fields. An L-shape is entered as the overall rectangle minus its cut-out corner; a T, U or any odd assembly of straight walls is entered as combined rectangles, one per row — the preview draws the pieces so you can check them against the room. And for genuinely weird geometry — angled walls, bays, curves — draw the room in the Gridsnap editor and read the exact m² off the plan.
Should I order by area or by packs?
By packs — flooring is sold in sealed packs, so the quantity you actually buy is the pack count rounded up, and the calculator shows the bought area so you can see the rounding. Keep a spare pack's worth of offcuts for future repairs; a discontinued décor is impossible to patch later.
Does the room area include skirting or underlay?
Underlay is bought for the same area as the floor, so the "with waste" figure works for it too. Skirting is bought by perimeter length, not area — for this room that is the two side lengths added and doubled, minus door openings.
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Measure once — on a plan
Draw the room in exact millimetres and the area, perimeter and every future quantity fall out of the drawing. Free, no account needed.