Disclosed are various embodiments for costing Raw-Device Mapping (RDM) disks. A pseudo-datastore is created. The pseudo-datastore represents the RDM disk. The RDM disk includes a mapping file that exposes direct access to a disk identified by a logical unit number (LUN). A unit rate is assigned to the pseudo-datastore, the unit rate representing a cost per unit of storage provided by the RDM disk. Usage of the RDM disk is monitored. A cost is calculated for the usage of the RDM disk for a period of time based on the unit rate assigned to the pseudo-datastore.