About NexLookup

NexLookup provides free medical coding and billing lookup tools for revenue cycle management (RCM) professionals.

• ICD-10-CM diagnosis code lookup from the official CMS order file
• CARC / RARC denial and remittance advice remark codes
• NPI Registry live search via the CMS NPPES API

No protected health information (PHI) is collected, stored, or transmitted. NPI searches are proxied live and not cached.

This tool is for educational and professional reference. Always verify codes against official sources for billing decisions.