What is Credit Card Validator?

Check if a card number passes the Luhn algorithm and detect the card brand.

How do I use Credit Card Validator?

Type or paste your data into the field on this page and press the button. The result is calculated instantly in your browser — nothing is uploaded.

Is Credit Card Validator free?

Yes, Credit Card Validator is completely free. No signup, no downloads and no usage limits.

Credit Card Validator

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Verify any card number with the Luhn check-digit algorithm and detect the brand (Visa, Mastercard, Amex and more). Numbers are processed locally and never stored. Free.

Card number

The number is checked locally with the Luhn algorithm. It only proves the number is well-formed — it never tells whether the card is active or belongs to someone.

How does card validation work?

Card numbers are checked with the Luhn algorithm, a checksum formula. Starting from the right, every second digit is doubled, values above nine are reduced, and the total must end in zero. Most card numbers worldwide follow this rule.

What does this tool check?

A number is reported as valid only when the length looks correct and the Luhn checksum passes. The tool also detects the brand from the first digits, such as Visa, Mastercard, American Express, Discover and JCB.

Can it detect an active card?

No. The Luhn algorithm only proves the number is structurally valid. It cannot tell whether the card is active, has money, or belongs to a real person. Never enter a real card you do not own.

Where is it useful?

Checking whether a card number was typed correctly in forms and sign-ups.
Generating and verifying test card numbers while building payment UI.
Confirming that numbers on old receipts are well-formed.

Is my card number stored?

No. Validation happens instantly in your browser with simple arithmetic. The number is never sent anywhere, so it is safe to test even payment cards you own.

Frequently Asked Questions

What is Credit Card Validator?
Check if a card number passes the Luhn algorithm and detect the card brand.
How do I use Credit Card Validator?
Type or paste your data into the field on this page and press the button. The result is calculated instantly in your browser — nothing is uploaded.
Is Credit Card Validator free?
Yes, Credit Card Validator is completely free. No signup, no downloads and no usage limits.