Aside from validation, implement additional layers of fraud detection:

Here’s a simple example of how to use it:

return 'unknown';

Are you integrating this into a (like Laravel or WooCommerce)?

To turn a basic validator into an advanced fraud-prevention script, integrate a third-party BIN API (such as binlist.net). This allows your PHP backend to detect the exact issuing bank, card country, and card type (Debit vs. Credit), which you can cross-reference against your user's billing address to flag mismatch risks. I can help expand this logic into a web dashboard. Tell me: Do you need a to go with it? Should we integrate a third-party BIN lookup API ?

Malicious actors use automated scripts to test stolen cards. Protect your checker endpoints with rate limiters (such as Redis Token Bucket filters) or CAPTCHAs to block automated bot floods.