You can't trust sizes.
The really comfy Skechers ballet flats I'm wearing at the moment are a US 11 and measure 270mm along the inside. There's a pair of Zara bluchers in my shoe cabinet that also measure 270mm and are marked Euro size 41, but they're so agonisingly tight, I can barely get them on. Other size 41 pairs fit me perfectly. Apparently, if you buy a pair made in Italy, their supposedly EU-compliant size 41 is closer to a 40, I wouldn't be able to wear those, at all.
Your best bet is to measure the insole of a shoe that fits, and take a tape measure with you when you go shoe shopping. Online, there are sellers who list measurements in the item description. I prefer to buy from to those, rather than gamble.
And bear in mind whether you're going to be wearing socks in them, or not. Most men tend to wear tennis socks with trainers whereas a lot of women wear considerably thinner socks, if any, so even if it's a unisex shoe, the actual foot sizes it'll accommodate will differ across gender labels.
Nice to have another Nephilim fan on here. Hi.
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