The HPXML validator allows software developers to validate and inspect their tool's HPXML formatted data. Users can upload HPXML files and check these files against the HPXML schema and its standard datasets for compliance. The validation tool returns specific error messages with feedback on missing data elements. It also provides a searchable tree view of HPXML data to assist with navigating and inspecting errors.

The validation functionality is available as a website for testing and viewing individual files, or as a web service API that allows the validation to be called as part of a software workflow.