Super cute shoes!  Upper strap is adjustable with velcro, and the lower toe strap is fixed size.  I normally wear size 7-1/2, and my foot almost entirely covers the size 8 foot bed. Lower strap is a big loose, when means I occasionally want off the shoe - so be careful if you don't regularly wear shoes of this style.  Detail is beautiful and the shoe is really what I expected.  Glad I purchased it.