Credit Card Validator (Luhn + Brand)
Card numbers (PAN) embed a brand-specific Issuer Identification Number, an account number, and a final Luhn check digit. This tool: (1) detects brand from leading digits (Visa, Mastercard, Amex, Discover, JCB, Diners, UnionPay, Maestro), (2) checks the length matches that brand's spec, (3) runs the Luhn mod-10 checksum. Useful for client-side form validation — catches typos and obvious fakes before the payment processor sees them.
Enter a card number above.
⚠ Don't paste real cards into web tools. Use processor test numbers (e.g. Stripe's 4242 4242 4242 4242).
Detects brand from BIN/IIN prefix, validates length per brand, then runs Luhn mod-10. All local — nothing leaves your browser.
How to use
- Paste or type a card number. Spaces and dashes are stripped automatically.
- Watch the brand badge update as you type.
- ✓ valid means brand-correct length and Luhn pass. Real authorization still needs your processor.
Frequently asked questions
- Does Luhn-passing mean the card is real?
- No. Luhn only catches typos. A randomly generated Luhn-valid number is almost certainly not issued to anyone. Real validity needs your payment processor (Stripe, Adyen, etc) to attempt authorization.
- Which brands are detected?
- Visa, Mastercard, American Express, Discover, JCB, Diners Club, UnionPay, and Maestro — by leading-digit pattern. Some cards (e.g. private-label store cards) won't match and show as 'unknown'.
- Why does Amex show 15 digits?
- Amex uses 15-digit PANs and a 4-digit CID (the security code). Visa/MC use 16-digit PANs and a 3-digit CVV. Discover/JCB are 16, sometimes 19.
- Is it safe to paste a real card number here?
- Computation runs entirely in your browser — nothing is sent over the network. That said, don't paste real cards into random web tools. Use test card numbers for validation testing (e.g. Stripe's 4242 4242 4242 4242).
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