Tool Help

What this NPI tool does
Validate National Provider Identifiers (NPIs) using the official check-digit algorithm (Luhn with an 80840 prefix).
What it checks
- Length is exactly 10 digits.
- Check digit matches the expected Luhn result.
- Shows both the expected and provided check digits.
Healthcare context
- Quickly checking NPIs during integration testing.
- Validating NPIs in sample data, mapping files, or ETL pipelines.
- Spotting obvious NPI data-quality issues before loading into systems.
This tool validates the structure and check digit only. It does not look up NPIs against NPPES or any external registry.

