Long time ago, I was in JR High School when a girl asked me about my size shoes. I answered her "size 3". She laughed at me and she called me "baby feet". :roll:
I wear anywhere from a 8 to 9 (US womens, depending on brand) and I wear a mens 7. My Muck boots are a mens 7.5 , got them a tad big for my thick socks I wear to work.
Size 12 women's American or men's tennis shoes 9 wide. They have a bit more room for the toes. I'm proud of my BIG feet. I earned them with kick-boxing my older brothers.
I usually start at around 10 and decide then if I need to go larger or smaller, and this is US also since I live in the US and have bought almost every pair of shoes I ever owned in the US. I actually focus more on the socks though. Those are much more interesting to me than shoes. Shoes tend to be too restrictive. I just wear them when it's required or I'm mowing the lawn.