I ordered size small in F-21.
I loved this dress and tried it on as soon as I got it for Christmas in front of my grandparents and everything. Knowing it was a swing dress I spun as soon as I had it on. When I spun, everyone could see my underwear. Thankfully I only had family over so it only made me more excited. This dress is so fun to spin in, just make sure you wear spandex or something under it. There is a full skirt and this is very much a swing dress. I also wore this dress dancing and every time someone twirled me I had to make sure my arm was down to keep from flashing everyone. Just be aware. The pattern is pretty. The fabric is great quality. It has weight to it and it's got just the right amount of stretch. The cut is flattering on a lot of different body types. I can't find any fallouts of this dress. I LOVE IT. I got another one in F-11 and it's pretty too. I have another dress from a different company but I like my GRACE KARIN dress better. The skirt just does it for me. One of the belt loops came of but it didn't matter because I put the belt at my natural waist anyways.
Get this dress! You won't regret it!