How Korean shoe sizes work
Korean shoe sizes are simply the length of the foot in millimetres. A 260 is made for a foot about 260 mm (26.0 cm) long, and sizes move in 5 mm steps: 255, 260, 265 and so on. The same number is used for men, women and children, so there is no separate women's scale to learn.
Korea shares this system with Japan, where identical sizes are written in centimetres (26.0 instead of 260). Both follow the Mondopoint idea behind the ISO 9407 standard: label the shoe with the foot it is meant to fit rather than with an arbitrary number. In the centimetre charts most brands publish, a US men's size goes up by one for every 10 mm (the strict US step is a third of an inch, about 8.5 mm), and a US women's size does the same from a different starting point, so most conversions are a quick subtraction.
Converting Korean mm to US sizes
The chart on this page follows the generic convention most Korean retailers use for US conversions. For men, US size = (mm − 180) ÷ 10, so 260 mm is a US men's 8, 270 is a 9 and 280 is a 10. For women, US size = (mm − 170) ÷ 10, so 230 mm is a US women's 6, 240 is a 7 and 250 is an 8.
Some brands label unisex shoes with a 1.5-size gap between men's and women's instead of 1.0. If a listing shows “M 8 / W 9.5”, that brand lists women's sizes half a size higher than this chart. Kids' sizes continue the men's scale downward: a youth 7Y is the same shoe as a men's 7 (250 mm), and 1Y follows 13.5C.
How to measure your foot
Stand on a sheet of paper with your heel against a wall, wearing the socks you plan to wear with the shoes, and mark the tip of your longest toe. Measure from the wall edge of the paper to the mark in millimetres. Measure both feet and use the longer one; a difference of a few millimetres between feet is common.
Your Korean size is that length rounded up to the next 5 mm. Many Korean shoppers then add 5–10 mm for sneakers and running shoes to leave room in the toe, and buy dress shoes or loafers at the measured length. Width is not part of the Korean number. US shoes come in widths such as D or 2E, while most Korean-market shoes come in a single width.
Why the same number fits differently across brands
Two shoes labelled 260 can fit differently because the number describes the foot, not the shoe. Each brand builds on its own last (the foot-shaped form a shoe is made around), so toe-box shape, heel width and internal length vary. Athletic shoes often run small and are bought a half size up; leather dress shoes are usually bought true to size; slip-ons and boots follow their own patterns.
Korean product pages help with this. Look for a “실측” (actual measurements) table listing the insole length in millimetres, and for reviews that say “정사이즈” (true to size), “크게 나왔어요” (runs large) or “작게 나왔어요” (runs small). When in doubt, buy from a seller that offers free exchanges.
Quick reference: the most common sizes
These are the conversions people look up most often, using the chart convention above.
- 230 mm = US women's 6
- 240 mm = US women's 7 or US men's 6
- 250 mm = US women's 8 or US men's 7
- 260 mm = US men's 8 or US women's 9
- 270 mm = US men's 9 or US women's 10
- 280 mm = US men's 10 or US women's 11