Medplum is based on the [FHIR API](https://www.hl7.org/fhir/R4/).

Medplum is "FHIR Native," using version 4.0.1 (aka R4), meaning the service stores data in the actual FHIR format, documented [here](/content/docs/api/fhir/resources/index.html).

Medplum also implements [custom resource types](/content/docs/api/fhir/medplum/index.html) to handle user management, authentication, and authorization.

The base URL for hosted Medplum is [https://api.medplum.com/fhir/R4](https://api.medplum.com/fhir/R4)