[Terr_]

> the number 0 since it looks so close to the letter 0.

Just throwing this out there in case the problem comes up again: https://en.wikipedia.org/wiki/Base58

[SyneRyder]

It's also worth skipping out the letters S and number 5, the letter G and number 6, and the letter B and number 8. I also omit vowels to avoid accidentally creating words in serial codes.

[bonesss]

I autogenerate passwords exclusively using lower case 'L's, the letter i in both cases, the number 1, and pipe characters.

[gspetr]

There's room for improvement. What about the "!"? Gotta catch those folks with poor eyesight.

[jimktrains2]

Also Base32, which has more out-of-the-box support:

https://en.wikipedia.org/wiki/Base32#Crockford.27s_Base32

[mark-r]

That's a good start, but if the string is meant to be typed by hand it would be better to be case insensitive. Some kind of base 32 encoding would be appropriate.