Why Doesn't Birkenstock Make a UK Size 6?

It does feel like a jump from 5.5 UK to 7 UK. But Birkenstock size their base on euro sizes and make a best guess for the conversion to UK. if you know your Birkenstock size once, things are easy for you but if you are generally an exact size 6, most of our customers go for a 39. If you like them a little looser, you can step up to 40.

Full Birkenstock size guide here
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