Measure your hat size yourself
Measure size
Place the tape measure backwards around your head at forehead height above your eyebrows. The number of centimeters determined in this way gives you your hat size. As a guideline, a hat sits approximately 1 finger's width above the ears. Further down it sits on the ears and is too big, further up it becomes too small.
If you don't have a tape measure at hand, you can also put a non-stretchy band around your head and then measure it with a ruler. It's best to measure at least one more time.
When a hat is a little too big
There are hat cork inserts for this option. These are simply placed in the inner band of the hat - ideally on the back and this makes the hat approx. 1/2 size smaller.
Size Chart
Here is a table for international sizes:
Size (in cm | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 |
International | XS | S | S | M | M | L | L | XL | XL |
US | 6 3/4 | 6 7/8 | 7 | 7 1/8 | 7 1/4 | 7 3/4 | 7 1/2 | 7 5/8 | 7 3/4 |