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Room Area Calculator

Rectangular, L-shaped or circular rooms — exact area, plus how many flooring boxes you'll need with a waste allowance built in.

✓ Free to use ✓ 3 room shapes ✓ Flooring box estimate ✓ Shareable results
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Flooring estimate
Room Area
With Waste Allowance
Flooring Boxes Needed

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Measuring an L-shaped room

The simplest way to measure an L-shape is as a full rectangle minus the missing corner: measure the room as if it were a complete rectangle (main length × main width), then subtract the area of the cut-out corner (its own length × width). This calculator does exactly that.

Why box coverage varies so much

Flooring box coverage isn't standardised — laminate boxes typically cover 1.8-2.5 m², vinyl plank boxes vary similarly, and tile boxes depend entirely on tile size. Always check the specific coverage printed on your chosen product's packaging and adjust the field above rather than trusting a generic default for anything beyond a rough first estimate.

Worked example

An L-shaped room measured as a 5m × 4m rectangle with a 2m × 1.5m corner missing: total area is 17 m². With a 10% waste allowance (18.7 m²) and boxes covering 2.2 m² each, you'd need 9 boxes.

Always round up to the nearest full box — flooring can't be bought in fractional amounts, and offcuts from one box often can't be reused elsewhere in the room depending on the plank/tile layout pattern.

Frequently Asked Questions

How much extra flooring should I buy for waste?+
10% is a standard allowance for a simple rectangular room laid straight. Complex layouts, diagonal patterns, or rooms with lots of alcoves and doorways often need 15-20% to account for extra cuts and offcuts.
What if my room has more than one cut-out corner?+
Calculate the full bounding rectangle, then subtract each missing corner separately and sum the deductions — or break the room into multiple simple rectangles and add their areas together instead. Read the full L-shape measuring method →
Does this account for skirting boards or thresholds?+
No — this calculates floor area only. Skirting board length and door threshold trims need to be measured and ordered separately.

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