Long Form Date (Month Name, English) Regex for PHP

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching long form date (month name, english), ported and verified for PHP. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your PHP project — whether you're validating in a Laravel validator, a WordPress plugin, or a standalone PHP script.

Php Implementation

<?php
// Long Form Date (Month Name, English)
// ReDoS-safe | RegexVault — Localization > Date Formats

define('LONG_FORM_DATE_MONTH_NAME_ENGLISH_PATTERN', '/^(?:((?:[0-2]?[0-9]|3[01])(?:st|nd|rd|th)?)\s+(January|February|March|April|May|June|July|August|September|October|November|December)\s+((?:19|20)[0-9]{2})|(January|February|March|April|May|June|July|August|September|October|November|December)\s+([0-2]?[0-9]|3[01])(?:st|nd|rd|th)?,?\s+((?:19|20)[0-9]{2}))$/');

function validate_long_form_date_month_name_english(string $input): bool {
    return (bool) preg_match(LONG_FORM_DATE_MONTH_NAME_ENGLISH_PATTERN, $input);
}

// Example
var_dump(validate_long_form_date_month_name_english("15 January 2024")); // bool(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 PHP developers because especially relevant in PHP where PCRE backtracking limits can trigger silent failures on malicious input. 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

Matches both UK order (D Month Y) and US order (Month D, Y). The ordinal suffix (st, nd, rd, th) is optional. Month names are case-insensitive. Abbreviated month names (Jan, Feb) require a different pattern.