Centimetres, inches, and the conversion nobody does
Suppliers publish centimetres. Shoppers think in inches. Every chart now prints both.
Every chart in this catalogue arrives in centimetres, because that is what the suppliers publish. Almost every shopper reads her own measurements in inches, because that is what her tape and her sizing habits use.
So every measurement on this site prints both, from the same source number. 72 cm is 28.3 in. We do not round to a size, and we do not let a rounded inch drive a recommendation — the centimetre value is the authority and the inch is there so you can check it against something you already know.
The conversion is exact to one decimal place. Anything more precise than that would be implying a measurement the garment does not have.