I wear a size 8, but after ordering size 38 (always being told size 8 is 38) I realized I need a size 39.  I LOVE these flip flops.  SO COMFORTABLE!!!  Living in the Sunshine State I live in flip flops, Birkenstock flip flops will be my new obsession.  I get many compliments.  They are also easy to clean, if wet, just wipe down with paper towel.  Great arch support and toe grip, but that's what Birkenstock is known for.  Wish I bought Birkenstock years ago.