US National Provider Identifier (NPI) Regex for Python

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching us national provider identifier (npi), ported and verified for Python. Identity and credential patterns need both correctness and safety, since they're frequent targets for adversarial input. The snippet below is ready to drop into your Python project — whether you're validating in a Django view, a FastAPI endpoint, or a standalone data processing script.

Python Implementation

# US National Provider Identifier (NPI)
# ReDoS-safe | RegexVault — Identity & PII > Health Identifiers

import re

us_national_provider_identifier_npi_pattern = re.compile(r'^[0-9]{10}$')

def validate_us_national_provider_identifier_npi(value: str) -> bool:
    return bool(us_national_provider_identifier_npi_pattern.fullmatch(value))

# Example
print(validate_us_national_provider_identifier_npi("1234567893"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Identity & PII > Health Identifiers category and carries a ReDoS-safe certification. That matters for Python developers because particularly important in Python web servers where CPU-bound regex operations can stall concurrent request handling. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

NPI is the US healthcare provider identifier under HIPAA. Issued by CMS (Centers for Medicare and Medicaid Services). The last digit is a Luhn check digit (applying the Luhn algorithm with prefix 80840 prepended to the 9-digit base). Type 1 NPI = individual, Type 2 = organization.