Clothing Size Converter Formula

Understand the math behind the clothing size converter. Each variable explained with a worked example.

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Formulas Used

UK Size

uk_size = us_size + 4

EU Size

eu_size = us_size + 30

Letter Size Index

xs_to_xl = us_size <= 2 ? 1 : (us_size <= 6 ? 2 : (us_size <= 10 ? 3 : (us_size <= 14 ? 4 : 5)))

Variables

VariableDescriptionDefault
us_sizeUS Women Size8

How It Works

Clothing Size Conversion (Women)

Approximate Size Chart

USUKEULetter 0-24-630-32XS 4-68-1034-36S 8-1012-1438-40M 12-1416-1842-44L 16-1820-2246-48XL

Important Note

Sizes vary significantly between brands and are not standardized. Always check the specific brand size chart. These conversions are general guidelines only.

Worked Example

Convert US size 8 to UK and EU.

us_size = 8
  1. 01UK size = 8 + 4 = 12
  2. 02EU size = 8 + 30 = 38
  3. 03Letter size: Medium (M)

Frequently Asked Questions

Are these conversions exact?

No. Clothing sizes are not standardized globally, and even within one country, brands use different sizing. These are approximate guidelines. Always consult the specific brand size chart.

What is vanity sizing?

Vanity sizing is when brands label clothes with smaller size numbers than historical standards. A modern US size 8 may have the measurements of a vintage size 12. This makes cross-brand comparison difficult.

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