github.com/rstandt/terraform@v0.12.32-0.20230710220336-b1063613405c/website/docs/configuration/functions/uuid.html.md (about) 1 --- 2 layout: "functions" 3 page_title: "uuid - Functions - Configuration Language" 4 sidebar_current: "docs-funcs-crypto-uuid" 5 description: |- 6 The uuid function generates a unique id. 7 --- 8 9 # `uuid` Function 10 11 -> **Note:** This page is about Terraform 0.12 and later. For Terraform 0.11 and 12 earlier, see 13 [0.11 Configuration Language: Interpolation Syntax](../../configuration-0-11/interpolation.html). 14 15 `uuid` generates a unique identifier string. 16 17 The id is a generated and formatted as required by 18 [RFC 4122 section 4.4](https://tools.ietf.org/html/rfc4122#section-4.4), 19 producing a Version 4 UUID. The result is a UUID generated only from 20 pseudo-random numbers. 21 22 This function produces a new value each time it is called, and so using it 23 directly in resource arguments will result in spurious diffs. We do not 24 recommend using the `uuid` function in resource configurations, but it can 25 be used with care in conjunction with 26 [the `ignore_changes` lifecycle meta-argument](../resources.html#ignore_changes). 27 28 In most cases we recommend using [the `random` provider](/docs/providers/random/index.html) 29 instead, since it allows the one-time generation of random values that are 30 then retained in the Terraform [state](/docs/state/index.html) for use by 31 future operations. In particular, 32 [`random_id`](/docs/providers/random/r/id.html) can generate results with 33 equivalent randomness to the `uuid` function. 34 35 ## Examples 36 37 ``` 38 > uuid() 39 b5ee72a3-54dd-c4b8-551c-4bdc0204cedb 40 ``` 41 42 ## Related Functions 43 44 * [`uuidv5`](./uuidv5.html), which generates name-based UUIDs.