S-M-L, numeric and measurement-based labels all describe the same body differently.
Three families of labels
Sizing labels fall into alpha (S, M, L), numeric (US 8, EU 38) and measurement-based (waist 32, neck 40) families. Alpha labels compress a wide range of bodies into a few buckets, which is why they vary most between brands.
Asian sizing
Japanese, Korean and Chinese systems typically run smaller than Western equivalents for the same label. Japanese womenswear uses odd numbers, Korean sizing commonly uses the 44-88 scale, and Chinese labels often encode height and bust in centimetres.
Regional derivations
Australian womenswear generally aligns with UK numbering. Italian sizing runs above EU numbering, and French sizing tends to match EU. Knowing which family a label belongs to removes most of the guesswork.
Building a personal size profile
Keep a note of your bust or chest, waist, hips, inseam, foot length in centimetres, head and hand circumference. With those numbers any converter or brand chart becomes usable, regardless of the label system in front of you.
Frequently Asked Questions
Is there a global sizing standard?
Standards such as ISO and EN exist, but adoption is voluntary and inconsistent, so labels still differ between brands.
Are alpha sizes unreliable?
They are broader by design. Measurement-based labels are more precise.