Sizing Without the Guesswork
Why conversion tables fail, which measurements actually predict fit, and how to read a Chinese size chart in under a minute.
Updated 2026-10-17
Conversion tables average the wrong thing
A conversion table maps a letter to a letter, and garments are not average. Two manufacturers using the same letter can differ by several centimetres.
That is why the same buyer can be a medium from one seller and a large from another, and why the letter is the least useful number on the page.
Measure what you already own
Lay a garment that fits flat, then measure chest, length and shoulder. For footwear, use insole length in millimetres rather than a size label.
Those three or four numbers predict fit better than any chart, because they describe your body rather than a manufacturer's convention.
Reading a Chinese size chart
Charts usually give flat measurements, meaning the garment laid flat rather than the body circumference. Doubling chest width gives the chest circumference.
Check whether the chart is for the garment or the wearer. Getting this backwards is the second most common sizing mistake after trusting the letter.
Fabric changes fit
Knit and stretch fabrics forgive a centimetre or two. Rigid woven fabrics, denim especially, do not, and shrinkage varies by fabric.
Ask or check whether measurements are pre-wash. On untreated denim that difference is the whole sizing decision.
When to size up
Size up for rigid fabrics, for anything you will layer, and for footwear if you are between insole lengths.
Do not size up for knitwear you want fitted, and do not assume a size up fixes a shape problem. Measurement first, then judgement.
FAQ
Is Asian sizing always smaller?
Often, but not uniformly, and the difference varies by category. Measurement is the only approach that works across all of them.
What if the listing has no chart?
Ask the seller, or skip the listing. Guessing is the most avoidable mistake in the whole process.
Do reviews help with sizing?
Yes, and they are often the most useful part of the page. Look for buyers stating their height, weight and what they ordered.