How big should I size my Birkenstocks? Should I leave extra space behind my heel? [URL=https://www.birkenstockukoutlet.com/]Birkenstock UK Outlet[/URL] A: Birkenstock fitting could be a very personal thing, as some wearers love to sizing a little large by leaving more space behind the hindfoot and while watching toes, while others like to dimensions slightly more compact making it possible for a snug, nearly hug-like suit. When thinking about the length of your Birkenstocks, the most crucial thing to look at is how the arches of the sandals struck your feet.