> For the complete documentation index, see [llms.txt](https://docs.verygoodsecurity.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verygoodsecurity.com/vault/developer-tools/apis/vault-api/alias-formats.md).

# Alias-Formats

| Format                               | Description                                                                                   |
| ------------------------------------ | --------------------------------------------------------------------------------------------- |
| UUID                                 | Generic - VGS Alias (Default) - tok\_sandbox\_xxxxxxxxxxxxxxxxxxxxxxxxx                       |
| NUM\_LENGTH\_PRESERVING              | Generic - Numeric Length Preserving - xxxxxxxxxxxxxxxx                                        |
| FPE\_SIX\_T\_FOUR                    | Payment Card - Format Preserving, Luhn Valid (6T4) - \<first\_six>xxxxxx\<last\_four>         |
| FPE\_T\_FOUR                         | Payment Card - Format Preserving, Luhn Valid (T4) - xxxxxxxxxxxx\<last\_four>                 |
| PFPT                                 | Payment Card - Prefixed, Luhn Valid, 19 Digits Fixed Length - xxxxxxxxxxxxxxxxxxx             |
| NON\_LUHN\_FPE\_ALPHANUMERIC         | Payment Card - Format Preserving - Non Luhn Valid - xxxxxxxxxxxxxxxx                          |
| FPE\_SSN\_T\_FOUR                    | SSN - Format Preserving (A4) - xxx-xx-\<last\_four>                                           |
| FPE\_ACC\_NUM\_T\_FOUR               | Account Number - Numeric Length Preserving (A4) - xxxxxxxxxxxx\<last\_four>                   |
| FPE\_ALPHANUMERIC\_ACC\_NUM\_T\_FOUR | Account Number - Alphanumeric Length Preserving (A4) - xxxxxxxxxxxx\<last\_four>              |
| GENERIC\_T\_FOUR                     | Generic - VGS Alias Last Four (T4) - tok\_sandbox\_xxxxxxxxxxxxxxxxxxxxxxxxx\_\<last\_four>   |
| RAW\_UUID                            | Generic - UUID - xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx                                         |
| ALPHANUMERIC\_SIX\_T\_FOUR           | Numeric - Include Alphanumeric, 19 symbols length (6T4) - \<first\_six>xxxxxxxxx\<last\_four> |
| VGS\_FIXED\_LEN\_GENERIC             | Generic - VGS Alphanumeric Fixed Length, 29 characters - vgsxxxxxxxxxxxxxxxxxxxxxxxxxx        |


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