# Tag mapping

Tags are key-value pairs used to organize and provide additional context to the cost data.

In Cloud Cost Management, the Project and Environment fields are derived from the tags’ values. On the Tag Mapping page, you can customize how the tags are parsed by entering the keys you use for denoting a project or an environment.

For example, with the configuration of the following screenshot, the values of tags with key user:project or project will be used to populate the Project field, and the values of tags with key env will populate the Environment field.

Tag Mapping Selection

If selecting several tag keys is not enough for your use case, you can specify a regular expression in the Advanced tab instead. For example, using the configuration of the following screenshot, the key env will again be used for the Environment field, but the same will happen with keys Env, environment, etc.

Tag Mapping Advanced