--- page_title: v4 - uuid - Functions - Configuration Language description: The uuidv4 function generates a unique id. --- # `uuidv4` Function `uuidv4` generates a unique identifier string. The id is a generated and formatted as required by [RFC 4122 section 4.4](https://tools.ietf.org/html/rfc4122#section-4.4), producing a Version 4 UUID. The result is a UUID generated only from pseudo-random numbers. This function produces a new value each time it is called, and so using it directly in resource arguments will result in spurious diffs. We do not recommend using the `uuidv4` function in resource configurations. ## Examples ```shell-session > uuidv4() b5ee72a3-54dd-c4b8-551c-4bdc0204cedb ``` ## Related Functions - [`uuidv5`](/docs/templates/hcl_templates/functions/uuid/uuidv5), which generates name-based UUIDs.