I'm usually a size 5-6 in regular shoes and size 6.5 in heels/boots. This might be because I have slightly wide-set feet. But with all my other ankle boots I'm usually good with a size 6. These actually run small as other reviewers have mentioned. So I ended up having to exchange them for a size 7! I couldn't even get my feet all the way in the size 6 so I wasn't sure if a half size would be enough so I ordered size 7. They are a TAD bit big. I guess the perfect size for me personally would've been a 6.75 hahaha. If I wear these with just tights, they would probably slip off at one point... But nothing a pair of socks on top can't fix. I wore these out with tights and a pair of socks on top and they fit perfectly. They are extremely comfortable and really cute! I received many compliments. I like them a lot! But save the trouble of exchanging them and go up at LEAST half a size. If you have narrow feet a half size up should be sufficient but if you have wider feet, a whole size up might be better.