Every size dispute starts with two different questions being treated as one. Body measurements describe
the person. Garment measurements describe a piece of clothing lying flat. A 56 cm chest is not the same
as a 56 cm chest width on a shirt, because the flat width is half the circumference.
To read oopbuy size charts, find the unit first. Charts use centimetres and inches inconsistently, and
1 inch equals 2.54 cm. Then check what each line means: chest width measured across the front, or chest
circumference for a body; waist relaxed, or waist stretched; length from a high point shoulder or from
the collar. Only compare numbers that describe the same thing.
Do the comparison with clothes you own
Lay a garment that fits you well on a table, smooth it flat and measure the same points the chart uses.
This removes body-shape guesswork and accounts for the drop-shoulder cuts common on relaxed pieces. If
the seller only publishes a body chart, add room for movement rather than picking your exact body
number.
For the oopbuy shoe size guide, start at the foot
Stand on paper, trace the foot and measure from the longest toe to the heel, then measure the widest
part across the ball of the foot. Do this late in the day when feet are slightly larger, and wear the
socks you plan to use. Compare that foot length with the shoe’s stated insole length, and remember
that a thick sock needs extra room.
There is no reliable all-purpose EU, US and UK conversion table, because running, skate and formal lasts
are built differently and individual sellers describe sizes their own way. Follow the specific product
page and the seller’s own wording rather than a chart you found elsewhere.
Two habits make the comparisons reliable. Keep one neutral garment as your measuring reference so every
chart is checked against the same baseline, and write the date beside each number, because knits relax
with wear and washing.