Enter each room's length and width, choose a waste factor that matches your layout, and the calculator adds up your total floor area, the area to order once overage is included, and — if you enter the coverage per box from your product's packaging — how many boxes to buy. All figures update live as you type.
How to measure a room, and why you order overage
Measure each room at its longest length and widest width, in the unit your supplier quotes in, and add it as its own row above — treat an attached closet, nook, or hallway as a separate room so nothing gets missed. It is normal, and expected, for the number you order to be larger than the number you measured: real installs lose material to cuts around doors, vents, and corners, to boards culled for visible defects, and to the box or two kept aside afterward so a future repair can be matched to the same dye lot rather than a newer, slightly different batch.
The waste factor is how that overage is expressed — as a percentage added on top of your measured area. A simple room laid in a straight grid wastes the least; cutting on a diagonal wastes more; and a herringbone or chevron pattern, with its repeating angled cuts, wastes the most. Treat the presets above as a starting point and round up rather than down when a room is unusually cut-up or the pattern is intricate.
Frequently asked questions
What is a waste factor, and why should I order extra flooring?
A waste factor is the extra flooring you buy beyond a room's exact square footage, to cover cuts around doors and corners, offcuts, boards you cull for defects, matching the dye lot if you need more later, and keeping a little attic stock for future repairs. Ordering exactly the measured area almost always leaves you short.
How much extra should I order — what waste factor should I use?
These are common industry rules of thumb, not a figure set by any standards body: roughly 5% for a simple, straight (grid) layout; about 10% for a diagonal layout, which needs more angled cuts; and about 15% for herringbone or chevron patterns, which waste the most material. Complex rooms with lots of corners, closets, or built-ins may need more than the flat rule of thumb suggests.
How do I measure a room for flooring?
Measure the room's overall length and width at the longest points, in feet and inches or in metres, and treat odd nooks, closets, or connected areas as separate rooms in the calculator so you can add each one. Round small fractions up rather than down, and measure in whichever unit your supplier quotes material in so the order matches.
How many boxes of flooring do I need?
Check the coverage per box printed on the product's packaging (in square feet or square metres), enter it in the calculator, and it divides your area-to-order by that coverage and rounds up — since a partial box still means buying a whole one.
Does this calculator tell me what a flooring job will cost?
No — this tool only calculates area and box counts, not price. Material and installation costs vary too much by region, product, and installer to estimate reliably here; ask a local supplier or installer for pricing once you know your area and box count.
Keep going: see our how-to-choose framework or the full guide library.
Educational tool — not professional advice. This calculator estimates area and box counts only; it does not estimate price, and it is not a substitute for a supplier's or installer's own measurement. Always confirm the final quantity with your supplier before ordering. Last verified: 21 July 2026. See our Disclaimer & Terms.