Korean Date Format (YYYY년 MM월 DD일) Regex for Python

What this pattern does

This page provides a well-structured, multi-part regular expression for matching korean date format (yyyy년 mm월 dd일), 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

# Korean Date Format (YYYY년 MM월 DD일)
# ReDoS-safe | RegexVault — Localization > Date Formats

import re

korean_date_format_yyyy_mm_dd_pattern = re.compile(r'^((?:19|20)[0-9]{2})년\s?(0?[1-9]|1[0-2])월\s?(0?[1-9]|[12][0-9]|3[01])일$')

def validate_korean_date_format_yyyy_mm_dd(value: str) -> bool:
    return bool(korean_date_format_yyyy_mm_dd_pattern.fullmatch(value))

# Example
print(validate_korean_date_format_yyyy_mm_dd("2024년 1월 15일"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Localization > Date Formats 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

Korean uses 년 (year), 월 (month), 일 (day). Spaces between the components are optional. The optional \s? handles both spaced and unspaced forms. Korea uses the Gregorian calendar exclusively for civil purposes.