Tool for encryption/decryption in Base91, an encoding based on 91 ASCII characters that limits the size of the encoded data.
Base91 Encoding - dCode
Tag(s) : Character Encoding
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Base91 (or BasE91) is an alternative to base64 but with an expanded alphabet to 91 characters: the 94 printable ASCII characters (from 0x21 to 0x7E) omitting -: dash (0x2D), \: backslash (0x5C) and ': apostrophe (0x27). It allows any binary data to be encoded into a character string composed only of printable characters (and therefore transmissible via text messaging, etc.)
Base91 encoding splits data into 13-bit binary packets (ie 2 ^ 13 = 8192 values) which are then encoded in 2 letters of the alphabet (which contains 91 characters and 91 ^ 2 = 8281).
Example: dCode string is coded xJ,Jc,A in Base91
The symbols used by the base are:
0 | A | 1 | B | 2 | C | 3 | D | 4 | E | 5 | F | 6 | G | 7 | H | 8 | I | 9 | J | 10 | K | 11 | L | 12 | M |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
13 | N | 14 | O | 15 | P | 16 | Q | 17 | R | 18 | S | 19 | T | 20 | U | 21 | V | 22 | W | 23 | X | 24 | Y | 25 | Z |
26 | a | 27 | b | 28 | c | 29 | d | 30 | e | 31 | f | 32 | g | 33 | h | 34 | i | 35 | j | 36 | k | 37 | l | 38 | m |
39 | n | 40 | o | 41 | p | 42 | q | 43 | r | 44 | s | 45 | t | 46 | u | 47 | v | 48 | w | 49 | x | 50 | y | 51 | z |
52 | 0 | 53 | 1 | 54 | 2 | 55 | 3 | 56 | 4 | 57 | 5 | 58 | 6 | 59 | 7 | 60 | 8 | 61 | 9 | 62 | ! | 63 | # | 64 | $ |
65 | % | 66 | & | 67 | ( | 68 | ) | 69 | * | 70 | + | 71 | , | 72 | . | 73 | / | 74 | : | 75 | ; | 76 | < | 77 | = |
78 | > | 79 | ? | 80 | @ | 81 | [ | 82 | ] | 83 | ^ | 84 | _ | 85 | ` | 86 | { | 87 | | | 88 | } | 89 | ~ | 90 | " |
Joachim Henke claims it was invented in 2005, see here
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