This review is my attempt to bring some clarity to the sizing for these (O'Neill Reactor Reef Boot). First of all, be aware that the sizing is listed in men's sizes. Before I get deeper into the sizing, I want to address the issues I have with the current reviews as a whole (BTW, I appreciate all of them): 1. Gender - Many of the reviews state to size up or down, but most people don't state their gender. Because women's shoe sizes are typically a full size larger then men's, stating to size up or down without stating gender is arbitrary. 2. Shoe Size - A lot of the reviewers compared these to their typical shoe size, but this is a very subjective statement because shoe sizing itself is very subjective. For example, in my experience, basketball shoes run a bit tighter than running shoes, but different brands of [same size] running shoes fit differently as well. I'm not sure if this is because of the different materials used, design, or a lack of standardization. 3. Fit - Many of the reviews stated that they "fit good", but that is also a subjective statement based on one's preferred fit, thus not overly helpful by itself. Ok, now on to the sizing details. This is only an estimation based on my own measurements, but since the seller and/or Amazon has not provided this information, you'll have to take my word for it. I first ordered these for my wife, who normally wears a women's size 7 1/2 - 8. Because she will be using these with snorkeling fins, they needed to be nice and snug, and since there aren't half sizes, I opted to size down. Now, because these are listed in men's sizes, I order a size 6, which is equivalent to a women's 7. For reference, her bare foot is 9" from the tip of her big toe to the back of her heel. The size 6 (women's 7) reef shoes measure 9 1/2" on the outside. I didn't measure the inside, but roughly estimate 1/4" for material, which leaves 1/4" at the toe. She said it fits nice and snug, but not too tight, no slipping at the heel and just a little room at the toe. For myself, I had it in my mind that I wear size 14 (because I mostly do), so I ordered a 14 for myself. BTW, i'm a man if you haven't figured that out yet. When I got them, I tried them on and they were too big, which was really confusing because I wear a 14....at least I thought I did. Well, I do, but like I stated above, shoe sizing is very subjective. I immediately went and looked at all of my shoes and about half of them are size 13, the other half 14. All of them are Nike or Adidas and I could not determine any consistency based on brand, type, or material. I decided to measure my foot to get to the bottom of this, which confused me even more because my foot measured almost exactly 12" (11 15/16" to be perfectly exact). So why don't I wear a size 12 if my foot measures 12"??? Well, that's another story and I don't even really understand it....Google it if you really need to know. The size 14 reef shoes measure 12 1/2" on the outside. I know what you're thinking...if my wife's reef shoe measured 1/2" bigger than her foot and it fit snug, then how were mine too big??? Well, I don't have an answer for that....like I said, this all based on measurements taken at different times with a tape measure, so it's not 100% accurate. This is also where personal preference comes into play. I'm hoping you can take what i've stated here and make an educated decision. Anyway, so I exchanged the 14 for a 13 and that fits much better. They are very snug, but I wouldn't want them any tighter as my toe is pretty darn close to the front tip. The nice thing is that the neoprene allows a good amount of flexibility, which I think i'm taking advantage of, but this is much better than the 14 for my needs. The outside measurement of the size 13 is 12 1/8", so you can see that I don't have much room to spare, yet I think they will be just fine. Based on the measurements taken from my wife's size 6 and my 13 and 14, i've come up with a rough estimate of the sizing: Note: This is the external measurement...the internal measurement will be slightly less. Size 6: 9 1/2" Size 7: 9 7/8" Size 8: 10 1/4" Size 9: 10 5/8" Size 10: 11" Size 11: 11 3/8" Size 12: 11 3/4" Size 13: 12 1/8" Size 14: 12 1/2" I hope this helps...good luck!
