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Carpet & Flooring Area

Add cutting waste to the floor area: 5–10% for plain material, 15–20% if you lay on the diagonal or match a pattern.

Your numbers

Area needed

16.63m²

Area

15.12

Pyeong

4.57

Formula

Area needed = Length × Width × (1 + Waste allowance ÷ 100)

Rooms are rarely true rectangles. Measure the longest span and decide up front whether to include thresholds and the space under fitted units.

What to enter

InputDefaultAccepted range
Length (m)The measurement across, side to side.4.20 and up
Width (m)The measurement front to back.3.60 and up
Waste allowance (%)The extra bought to cover breakage and offcuts.100 ~ 50

Step by step

FormulaArea needed = Length × Width × (1 + Waste allowance ÷ 100)
With the default numbersArea needed = 4.2 × 3.6 × (1 + 10 ÷ 100)
AnswerArea needed = 16.63 m²

Quick reference table

Results when only Length (m) changes and everything else stays put.

Length (m)Area needed (m²)Area (m²)Pyeong
2.18.327.562.29
3.1512.4711.343.43
4.216.6315.124.57
6.324.9522.686.86
8.433.2630.249.15

What each result means

ResultAt default values
Area needed (m²)The area to actually buy, waste included.16.63
Area (m²)The space a shape covers — length squared.15.12
PyeongA Korean area unit; 1 pyeong is about 3.3058 m².4.57

Common mistakes

Rooms are rarely true rectangles. Measure the longest span and decide up front whether to include thresholds and the space under fitted units.

Glossary

Length
The measurement across, side to side.
Width
The measurement front to back.
Waste allowance
The extra bought to cover breakage and offcuts.
Area needed
The area to actually buy, waste included.
Area
The space a shape covers — length squared.
Pyeong
A Korean area unit; 1 pyeong is about 3.3058 m².

Frequently asked questions

Q. How is Carpet & Flooring Area calculated?

Area needed = Length × Width × (1 + Waste allowance ÷ 100) — Add cutting waste to the floor area: 5–10% for plain material, 15–20% if you lay on the diagonal or match a pattern.

Q. Can you walk through an example?

With Length 4.2m, Width 3.6m, Waste allowance 10%, the answer is Area needed 16.63m².

Q. What do I need to enter?

Enter Length, Width, Waste allowance. The result recalculates as you type, and an empty box counts as zero.

Q. How much does the answer move if I change a number?

Changing only Length (m) moves the answer to Length (m) 2.1 → Area needed (m²) 8.32 and Length (m) 8.4 → Area needed (m²) 33.26. The table below lays out five steps.

Q. How are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

Q. Anything to watch out for?

Rooms are rarely true rectangles. Measure the longest span and decide up front whether to include thresholds and the space under fitted units.

Related calculators

Keep your length units consistent across inputs — mixing centimetres and metres throws results far off.