Security Tools

Credit Card Validator

Validate credit card numbers using the Luhn algorithm and identify card type

Credit Card Validator

Luhn algorithm — format validation only

Test numbers:

Security Warning

This tool validates card number format only using the Luhn algorithm. Never enter real card numbers into any online tool. Format validation does not mean a card is active or funded.

Free Credit Card Validator

This free credit card validator checks whether a card number is structurally valid using the Luhn algorithm and identifies the card network (Visa, Mastercard, Amex, Discover). All validation runs in your browser — no data is transmitted.

Card types detected

Visa

Starts with 4 — 13 or 16 digits.

Mastercard

Starts with 51–55 or 2221–2720 — 16 digits.

American Express

Starts with 34 or 37 — 15 digits.

Discover

Starts with 6011, 644–649, or 65 — 16 digits.

FAQ

What is the Luhn algorithm?

A checksum formula used to validate credit card numbers. A number that passes is structurally correct but may not belong to a real account.

Does a valid number mean the card works?

No. Luhn validation only confirms correct formatting. It cannot check if the card is active or has funds.

Is it safe to enter my card number here?

Yes. This tool runs 100% in your browser. The number never leaves your device.

What test card numbers can I use?

Visa: 4111 1111 1111 1111. Mastercard: 5500 0000 0000 0004. These are structurally valid but not linked to real accounts.

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