German PLZ (Postleitzahl) Regex for Python

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching german plz (postleitzahl), ported and verified for Python. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. 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

# German PLZ (Postleitzahl)
# ReDoS-safe | RegexVault — Localization > Postal Codes

import re

german_plz_postleitzahl_pattern = re.compile(r'^(0[1-9]|[1-9][0-9])[0-9]{3}$')

def validate_german_plz_postleitzahl(value: str) -> bool:
    return bool(german_plz_postleitzahl_pattern.fullmatch(value))

# Example
print(validate_german_plz_postleitzahl("10115"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Localization > Postal Codes 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

German PLZ ranges: 01xxx-09xxx (east), 10xxx-14xxx (Berlin/Brandenburg), etc. The code 00000 is explicitly invalid. Also used in Austria (4 digits — different pattern) and Switzerland (4 digits). Use this only for Germany.