Size is a US10 however ASOS sizing runs big - more like a US12 in my opinion. My former sizing: Abercrombie Large, Reformation unknown, American Eagle XLarge, Old Navy Large, Asos 10 My current sizing: Abercrombie Medium; Reformation Large/10, American Eagle Large, Old Navy Medium, Asos unknown (havent purchased but prob an 8) This is my favorite dress and I no longer fit into it. I was so sad about it that I found someone selling it and repurchased it without knowing if the new size will fit. It’s a great dress for Spring and Summer and I want someone to love it!!