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tags: CESR, KERI
email: [e-mail]
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# CESR Selector Codes and Tables

| Selector | Size | Pad | Unq | Len | Format | Unique | Quad/Trip | Bytes |
|:---------:|:----:|:---:|:---:|:---:|------------:|-------------:|------------:|-----------:|
| | | | | | | | | |
| [A-Z,a-z] | 1 | %1 | 1 | * | $| 52| * | * |
| 0 | 2 | %2 | 1 | * | 0$| 64| * | * |
| 1 | 4 | %0 | 3 | * | 1$$$| 262,144| * | * |
| 2 | 5 | %1 | 4 | * | 2$$$$| 16,777,216| * | * |
| 3 | 6 | %2 | 5 | * | 3$$$$$| 1,073,741,824| * | * |
| 4 | 4 | 0 | 1 | 2 | 4$##| 64| 4,096 | 12,288 |
| 5 | 4 | 1 | 1 | 2 | 5$##| 64| 4,096 | 12,288 |
| 6 | 4 | 2 | 1 | 2 | 6$##| 64| 4,096 | 12,288 |
| 7 | 8 | 0 | 3 | 4 | 7$$$####| 262,144| 16,777,216 | 50,331,648 |
| 8 | 8 | 1 | 3 | 4 | 8$$$####| 262,144| 16,777,216 | 50,331,648 |
| 9 | 8 | 2 | 3 | 4 | 9$$$####| 262,144| 16,777,216 | 50,331,648 |
| - | 4 | 0 | 1 | 2 | -$##| 52| @4,096 | * |
| - | 8 | 0 | 2 | 4 | -0$$####| 4,096| @16,777,216 | * |
| - | 12 | 0 | 2 | 4 | -1$$########| 4,096| > @2x10^21 | * |
| _ | 4 | 0 | 1 | 2 | _$##| 52| @4,096 | * |
| | | | | | | | | |

`%` means the effective Base64 pad characters of the given length in the text version are replaced by the code. Otherwise the pad is the number of pad bytes added before conversion to the raw binary attached material to ensure the attached binary material ends on a 24 bit boundary.

`*` means length is determined by the unique code

`$` means a Base64 character [A-Z,a-z,0-9,-,_] used as part of a unique code

`#` means a Base64 digit as part of a base 64 integer that determines the number of following quadlets or triplets in the primitive

`@` means the number of members in the following group of composable groups or primitives where the length of each group member is determined by the unique code