Abbreviated Month Name (English) Regex for JavaScript

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching abbreviated month name (english), ported and verified for JavaScript. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your JavaScript project — whether you're validating in an Express middleware, a Next.js API route, or a client-side form.

Javascript Implementation

// Abbreviated Month Name (English)
// ReDoS-safe | RegexVault — Localization > Date Formats

const abbreviatedMonthNameEnglishRegex = /^(?:(0?[1-9]|[12][0-9]|3[01])[\-\s](Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)[\-\s]((?:19|20)[0-9]{2})|(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\s+(0?[1-9]|[12][0-9]|3[01]),?\s+((?:19|20)[0-9]{2}))$/i;

function validateAbbreviatedMonthNameEnglish(input: string): boolean {
  return abbreviatedMonthNameEnglishRegex.test(input);
}

// Example
console.log(validateAbbreviatedMonthNameEnglish("15-Jan-2024")); // 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 JavaScript developers because especially critical in long-running Node.js event loops where a ReDoS vulnerability can block the entire process. 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

DD-Mon-YYYY is common in Oracle databases and UK bank statements. Mon DD, YYYY is common in American printed documents. The month abbreviation is always 3 letters.