Nothing more simple! Take a meter tape. Then position the meter around your head where the hat would rest (in principle between 0.5 and 1 cm above the ears). Do not squeeze the meter too hard, otherwise you may make a measurement error.
Once the measurement is complete, find your size in the table below. If your main size falls in the middle of two sizes, choose the largest preference. The hat will be all the more comfortable.
If, in spite of everything, you want to reduce the size of your hat, we propose in our products size reductant cork strips.
Available sizes: S= 55 cm/M = 57 cm/L = 59 cm/XL = 61 cm