There are many factors which determine hat size and fit. The only guarantee to a perfect fit is to try the hat on and purchase that hat. That being said the chart below is a good aid in determining your hat size. If you are near the upper limit of a size it is usually best to go to the next size. It is easier to make a slightly large hat fit than one too small.
Foam size reducing tape is sent with each hat. To use just slip it inside the sweatband as needed. Though it can be adhered to the hat it works best if the paper backing is left on.
| HEAD CIRCUMFERENCE | AMERICAN SIZE | EUROPEAN SIZE | |
| From | To | ||
| 20-5/8" | 21" | 6 5/8 | 53 |
| 21" | 21-3/8" | 6 3/4 | 54 |
| 21-3/8" | 21-3/4" | 6 7/8 | 55 |
| 21-3/4" | 22-1/4" | 7 | 56 |
| 22-1/4" | 22-5/8" | 7 1/8 | 57 |
| 22-5/8" | 23" | 7 1/4 | 58 |
| 23" | 23-3/8" | 7 3/8 | 59 |
| 23-3/8" | 23-3/4" | 7 1/2 | 60 |
| 23-3/4" | 24-1/8" | 7 5/8 | 61 |
| 24-1/8" | 24-1/2" | 7 3/4 | 62 |
| 24-1/2" | 24-7/8" | 7 7/8 | 63 |
| 24-7/8" | 25-3/8" | 8 | 64 |