--- title: Feature Flag Naming Patterns --- :::info Availability Feature flag naming patterns is an **enterprise-only** feature released in Unleash v5.7. ::: A feature flag naming pattern is [JavaScript regular expression](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp) that is used to validate the name of a feature flag before the flag can be created. The pattern is defined in the project settings and is enforced when creating a new feature flag. The pattern is also enforced when creating a new feature flag via the API. Patterns are implicitly anchored to the start and end of the string. This means that a pattern is matched against the entire new feature flag name, and not just any subset of it, as if the pattern was surrounded by `^` and `$`. In other words, the pattern `[a-z]+` will be interpreted as `^[a-z]+$` and will match "somefeature", but will not match "some.other.feature". Feature flag naming patterns are defined on a per-project basis. In addition to the pattern itself, you can also define a an example and a description of the pattern. If defined, both the example and the description will be shown to the user when they are creating a new feature flag. ## Overview The naming pattern consists of three parts: