---
title: UUID
summary: null
url: https://www.fastly.com/documentation/reference/vcl/functions/uuid
---

The uuid module provides interfaces for generating and validating unique
identifiers as defined by [RFC 4122](https://tools.ietf.org/html/rfc4122).

Note that Version 1 identifiers, based on current time and host identity,
are currently not supported.

- [uuid.dns](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-dns/)
- [uuid.is_valid](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-is-valid/)
- [uuid.is_version3](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-is-version3/)
- [uuid.is_version4](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-is-version4/)
- [uuid.is_version5](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-is-version5/)
- [uuid.is_version7](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-is-version7/)
- [uuid.oid](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-oid/)
- [uuid.url](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-url/)
- [uuid.version3](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-version3/)
- [uuid.version4](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-version4/)
- [uuid.version5](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-version5/)
- [uuid.version7](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-version7/)
- [uuid.x500](https://www.fastly.com/documentation/reference/vcl/functions/uuid/uuid-x500/)