Fingerprint Quality Score (NIST NFIQ) Regex for Python

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching fingerprint quality score (nist nfiq), 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

# Fingerprint Quality Score (NIST NFIQ)
# ReDoS-safe | RegexVault — Identity & PII > Biometric & Physical

import re

fingerprint_quality_score_nist_nfiq_pattern = re.compile(r'^(?:100|[1-9][0-9]?|0)$')

def validate_fingerprint_quality_score_nist_nfiq(value: str) -> bool:
    return bool(fingerprint_quality_score_nist_nfiq_pattern.fullmatch(value))

# Example
print(validate_fingerprint_quality_score_nist_nfiq("0"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Identity & PII > Biometric & Physical 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

NFIQ2 (NIST Fingerprint Image Quality 2) scores fingerprint images 0-100, where 100 is best quality and 0 is unusable. Used in biometric enrollment systems, e-passport readers, and border control. Fingerprint data is biometric data — highest sensitivity classification.