Perfect fit!  I take a 5 1/2 - 6 size shoe & 36 - 37 Haflinger slipper depending on the cut.  The 36 in this slipper fits perfectly.  Great arch support  & I have ultra high arches.  The only thing I can see being a problem for some is the knit across the top is a smidge tight but I also have very high insteps & RA in my feet so it could be just me & I know that they will loosen up in short time.  These slippers are comfy & as cute as can be & the best part is they don't require a litter box!  I love Haflinger slippers (not a paid message).