## Try it out!

## Human-friendly? Duotrigesi-what?

32 digits, picked for the right balance of legibility, audibility, and information density. 0 or O? 1 or I? 5 or S? Doesn't matter; they're equivalent in Base32H. All the digits can be found on your typical keyboard, and are totally safe for URLs, filenames, and anything else that might not like special characters.

## Rationale

Base32H is handy for all sorts of use cases, and stacks up pretty strong against other number systems:

- More compact than hexadecimal (a 40-bit number needs only 8 Base32H digits v. 10 hexadecimal digits)
- No case-sensitive letters or punctuation like in Base64 (you can use Base32H in filenames without worry)
- No un-decodable letters like in other base-32 systems (any letter or numeral on a US keyboard will decode to a Base32H digit)
- Easier to encode byte-aligned data than with non-power-of-two-radix number systems (no wasted bits)

These traits make it an excellent choice for any situation where people need to reliably read numeric identifiers -- asset tags, product keys, public key fingerprints, user IDs, etc. -- and especially if that situation entails reading an identifier aloud to someone else.

## Implementations

Three official / reference implementations and counting (all free software under the ISC License), plus multiple community-contributed implementations.

## Digits

Value | Canonical | Aliases |
---|---|---|

0 | 0 | O o |

1 | 1 | I i |

2 | 2 | |

3 | 3 | |

4 | 4 | |

5 | 5 | S s |

6 | 6 | |

7 | 7 | |

8 | 8 | |

9 | 9 | |

10 | A | a |

11 | B | b |

12 | C | c |

13 | D | d |

14 | E | e |

15 | F | f |

16 | G | g |

17 | H | h |

18 | J | j |

19 | K | k |

20 | L | l |

21 | M | m |

22 | N | n |

23 | P | p |

24 | Q | q |

25 | R | r |

26 | T | t |

27 | V | v U u |

28 | W | w |

29 | X | x |

30 | Y | y |

31 | Z | z |