ICAO Machine-Readable Zone Line 1 (MRZ) Regex for Python

What this pattern does

This page provides a well-structured, multi-part regular expression for matching icao machine-readable zone line 1 (mrz), 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

# ICAO Machine-Readable Zone Line 1 (MRZ)
# ReDoS-safe | RegexVault — Identity & PII > Passport Numbers

import re

icao_machinereadable_zone_line_1_mrz_pattern = re.compile(r'^P[A-Z<]([A-Z]{3})([A-Z0-9<]{39})$')

def validate_icao_machinereadable_zone_line_1_mrz(value: str) -> bool:
    return bool(icao_machinereadable_zone_line_1_mrz_pattern.fullmatch(value))

# Example
print(validate_icao_machinereadable_zone_line_1_mrz("P<UTOERIKSSON<<ANNA<MARIA<<<<<<<<<<<<<<<<<<<"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Identity & PII > Passport Numbers 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

MRZ Line 1 for passports: document type (P) + subtype + 3-char issuing country + surname<<given names, padded with < to 44 chars total. Line 2 contains the passport number, nationality, DOB, sex, expiry, and check digits.