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How to Calculate Carpet

What is Carpet?

A carpet calculator determines how much carpet is needed for a room, including an allowance for wastage from cuts and seams. Carpet is typically sold by the linear metre in widths of 3m, 3.66m, or 4m.

Formula

Area (sq ft) = Length × Width | Area (m²) = Length × Width | Waste allowance: +10% for seams and cuts | Density affects durability

Step-by-Step Guide

  1. 1Calculate room area = Length × Width
  2. 2Add 10–15% for wastage and pattern matching
  3. 3Consider carpet width: standard rolls are 3m, 3.66m, or 4m wide
  4. 4Irregular rooms: divide into rectangles, sum areas, add wastage

Worked Examples

Input
Room 4m × 3.5m, no pattern
Result
Area = 14m²; with 10% wastage = 15.4m²; one strip from 4m wide roll works

Frequently Asked Questions

What is Carpet?

A carpet calculator determines how much carpet is needed for a room, including an allowance for wastage from cuts and seams. Carpet is typically sold by the linear metre in widths of 3m, 3

How accurate is the Carpet calculator?

The calculator uses the standard published formula for carpet. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Carpet calculator use?

This calculator works with inches, percentages, watts. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Carpet calculator use?

The core formula is: Calculate room area = Length × Width. Each step in the calculation is shown so you can verify the result manually.

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