CL Platform Ankle boots...

I have never tried those but I have the platform knee boot, which looks the same to me in the foot section. I sized up a half size and they are almost too roomy, but I have narrow feet, so take that into consideration. A lot of people size up in CLs but my feet are so narrow I don't seem to need to.
 
I have the tall boots as well in suede and I had to go a full size up. They are extremely comfortable I have worn them all day. My foot is of medium width.