I usually wear size 5, sometimes even 4.5. I ordered size 5 of this sandal, and it turns out that although part of the straps are adjustable, the other part are fixed, which made the sandal runs a little smaller, my toes can't reach the front. Maybe it's just me? As for the &#34;Breathable materials&#34;,which is actually Synthetic, I prefer leather a lot better. Luckily the best part of this is the memory foam footbed, very comfortable. Good for walking.