If you wear a men’s shoe greater than size 12 or a women’s shoe greater than size 11, you will have difficulty shoe shopping. Why? Because a bigger size means more inconsistency in width, length and depth.
Bigger sizes also usually don’t have half sizes, which makes finding the right fit even more dififcult.
Here are two pair of the same Keen shoes. A size 13 on the left and a size 12 on the right.
Notice how the size 13 is longer and more curved? This is clearly not one size larger, since a full size should only be 1/3″.
Bottom line, if your size falls into this category, you’ve got to pay particular attention to sizing and fit.
Dr. Jenny Sanders Shoe Blog 
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