Depending on the yarn and hook size you use you will have a different gauge. This pattern is written but is more of a guide with basic dimensions.

The last hat is done in stripes like this:
2 rows of each color starting at the sl st (top) and to avoid strange color changes at the bottom and weaving in ends =)
It also has a sc in the round brim, so I used the “w/o a brim” starting chain length