Credit Card Regex Javascript Validator

What is Credit Card Regex in JavaScript?

In JavaScript, a credit card regex is a regular expression used to verify whether an input string matches the format of a valid credit card number. These patterns help filter out incorrectly formatted numbers before backend validation or payment processing. They are especially useful for front-end form validation and protecting against invalid user inputs.

JavaScript-based credit card regex patterns are ideal for:

• Ensuring input format accuracy in forms before submission

• Instant client-side validation for smoother user experience

• Preventing non-numeric or improperly structured entries

Common Regex Patterns for Credit Cards

Credit card formats vary by provider. Below are common regex patterns used for each type:

// Visa (starts with 4, 13 or 16 digits)
^4[0-9]{12}(?:[0-9]{3})?$

Example: 4111111111111111

// MasterCard (starts with 51–55 or 2221–2720, 16 digits)
^5[1-5][0-9]{14}$|^2(2[2-9][0-9]{2}|[3-6][0-9]{3}|7[01][0-9]{2}|720[0-9]{2})[0-9]{10}$

Example: 5500000000000004

// American Express (starts with 34 or 37, 15 digits)
^3[47][0-9]{13}$

Example: 340000000000009

// Discover (starts with 6011 or 65, 16 digits)
^6(?:011|5[0-9]{2})[0-9]{12}$

Example: 6011000000000004

How to Validate Credit Card Numbers Using Regex in JavaScript

Here’s a complete working code example to validate a Visa card number using regex:

function isValidCreditCard(cardNumber) {
  const cardRegex = /^4[0-9]{12}(?:[0-9]{3})?$/; // Visa pattern
  return cardRegex.test(cardNumber);
}

// Example usage
const testCard = "4111111111111111";
console.log(`Is "${testCard}" valid?`, isValidCreditCard(testCard)); // true

Replace the regex pattern with MasterCard, Amex, or Discover to validate those types accordingly.

Real-World Use Cases

• Online Checkout Forms: Validate card number formats before sending to payment gateway.

• Mobile Apps: Reduce API calls by validating credit card input locally.

• Data Cleaning: Use regex patterns to clean up scraped or imported card data.

Pro Tips

• Use Luhn’s Algorithm along with regex for stronger validation—regex checks format, but Luhn checks actual card validity.

• Avoid storing raw credit card numbers; always tokenize or encrypt them.

• Always use HTTPS when handling sensitive inputs like credit card data.

• Combine with our Password Regex JavaScript Validator to create secure user flows.

• Use the JavaScript Regex Tester to test your patterns on the fly.

• For UUIDs in your backend or token system, check UUID Regex JavaScript Validator.

Combine with These Tools

Make your validation stronger and more comprehensive by pairing this tool with:

• JavaScript Regex Tester: Test and debug your regex patterns interactively.

• Password Regex JavaScript Validator: Ensure your user authentication is strong from the frontend.

• Email Regex JavaScript Validator: Validate emails in tandem with card inputs during checkout.

• SSN Regex JavaScript Validator: Useful for forms requiring identity verification.

• Mac Address Regex JavaScript Validator: Helpful for IoT apps collecting user device data.