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Online tool to instantly convert your FHIR resource between XML and JSON representation.
https://simplifier.net/validate : Online tool to check if a resource is valid FHIR and conforms to its profile(s).
validator.fhir.org: JSON FHIR validator (it is a web-based interface of FHIR Validator jar). It has an API.
http://registry.fhir.org is a central point to search for published FHIR Resources:
https://simplifier.net : The FHIR registry
Documentation
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