If you want random IDs to be human-readable (and human-communicatable), I'd just recommend base 32 or even base16. You don't actually save that many bytes from

If you want random IDs to be human-readable (and human-communicatable), I'd just recommend base 32 or even base16. You don't actually save that many bytes from base58 or base64 when it comes to short IDs. Case in point, the parent poster's base64 ID is 14 characters long. When encoded as base32 that's still only 17 characters (or 19 in base16), and now you have completely gotten rid of all notion of casing, which is annoying to communicate verbally.