Deciding what size to order: Measure your foot
Our sizing system looks weird but it's really simple. We call it Universal Footwear Sizing (UFS for short) and the two measurements signify [length.width] of the longest and widest part of your foot in mm.
How to measure: put your heel against a wall, measure the distance from the wall to the tip of your big toe, measure the width of the widest part of your foot.
When in doubt, go to the bigger size. Because the upper is made of a flexible neoprene like material, it will expand and contract to accommodate your foot. This means that your sizing doesn't have to be exact for the shoe to fit nicely.
Here's a short video of Nick explaining our sizing if you need more clarity: