US Short Date (M/D/YY) Regex for Python

What this pattern does

This page provides a well-structured, multi-part regular expression for matching us short date (m/d/yy), 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

# US Short Date (M/D/YY)
# ReDoS-safe | RegexVault — Localization > Date Formats

import re

us_short_date_mdyy_pattern = re.compile(r'^(0?[1-9]|1[0-2])/(0?[1-9]|[12][0-9]|3[01])/([0-9]{2})$')

def validate_us_short_date_mdyy(value: str) -> bool:
    return bool(us_short_date_mdyy_pattern.fullmatch(value))

# Example
print(validate_us_short_date_mdyy("1/15/24"))  # 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

2-digit years are ambiguous — 00-68 is commonly interpreted as 2000-2068, 69-99 as 1969-1999 (following Y2K windowing). Avoid 2-digit years in any data storage context. Capture groups: 1=month, 2=day, 3=2-digit year.