Base62

The base62 encoding scheme uses 62 characters. The characters consist of the capital letters A-Z, the lower case letters a-z and the numbers 0–9. It is a binary-to-text encoding scheme that represents binary data in an ASCII string format.

123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz = 58 characters = base58 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz = 62 characters = base62 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz+/ = 64 characters = base64

Base62 table
The Base62 index table :