Always remember that the hat can be rolled back... as pictured in the third photo ... so that it fits closer to your head...
My hats are measured so you CAN measure your head too... but, most of them are as my clothing is... one size fits most... there is a bit of stretch always in the brim, so, that going up or down one size is no problem... most of us know how hats fit us best... for me, I have realized my head is bigger than most... and I totally do not like tight hats (or bras, or pants, or shoes... or even hair bands)
Now if you decide the size is not right for you, on online orders, exchanging is fine... just message me for details.
How to Measure Hat Size:
Wrap a tape measure around your head, including the top of your ears, resting at the point where the hat will sit.