Here is a Chart to help you with your New Era Cap Size Selection

HAT SIZE 6 3/4     = 21 1/4inches      - 54cm
HAT SIZE 6 7/8     = 21 5/8 inches     - 54.9cm
HAT SIZE 7           = 22 inches           - 55.8cm
HAT SIZE 7 1/8     = 22 3/8 inches     - 56.8cm
HAT SIZE 7 1/4     = 22 3/4 inches     - 57.7cm
HAT SIZE 7 3/8     = 23 1/8 inches     - 58.7cm
HAT SIZE 7 1/2     = 23 1/2 inches     - 59.6cm
HAT SIZE 7 5/8     = 23 7/8 inches     - 60.6cm
HAT SIZE 7 3/4     = 24 1/4 inches     - 61.5cm
HAT SIZE 7 7/8     = 24 5/8 inches     - 62.5cm
HAT SIZE 8           = 25 inches           - 63.5cm