Credit Card Validator
Check a card number with Luhn and identify the network — nothing is stored.
Check a card number safely
Card numbers follow strict rules: a Luhn checksum plus network-specific prefixes and lengths. This validator checks both, which is exactly what a payment form does before it ever contacts a bank — useful for testing forms with sample numbers.
The well-known test number 4111 1111 1111 1111 validates as a 16-digit Visa. The tool reports the detected network and whether the Luhn check passes, without ever leaving your browser.
Private by design
Nothing is stored or uploaded, so the check happens purely on your device. It confirms format only — never whether a real card is active.
Frequently Asked Questions
Does this store my card number?
No. The number is checked entirely in your browser and is never saved or transmitted. Still, only test with numbers you are comfortable typing.
What does "valid" mean here?
That the number passes the Luhn checksum and matches a known network pattern — it does not mean the card exists or has funds.
Which networks are detected?
Visa, Mastercard, American Express, Discover, Diners Club, and JCB, based on their prefix ranges and lengths.
Browse the full set of free, private, in-browser tools.