What is the FHIR Validator?

The FHIR Validator is a free browser-based tool for parsing and validating FHIR R4 resources. Paste one resource to get a deep inspection — structure, issues, conformance score, field tree — or paste many resources at once and the tool automatically switches to a batch summary view with per-resource drill-down.

Everything runs in your browser. Your resources never leave your device, making it safe for use with PHI in development environments.

One Resource or Many — Same Tool

• Single resource: validate against R4, view the field tree, drill into nested structures.
• JSON array of resources: automatically split & batch-validated.
• Bundle: kept as a single resource (Bundle is one resource by design — the inspector handles its entries).
• Folder of .json files: drop a folder anywhere on the page.

Need to Define a FHIR Profile?

Build a formal FHIR conformance spec with Conformance Specs — field-level rules, shareable portals, and validation APIs.