Sécurité

Credit Card Validator

Check whether a credit card number passes the Luhn checksum, detect the card brand (Visa, Mastercard, Amex, Discover, JCB, Diners, UnionPay, Maestro), and see the expected check digit for any partial number.

Résumé de l'outil

Cet outil accepte une entrée structurée et renvoie une sortie déterministe dans le navigateur, sans envoi au serveur.

Nom de l'outil: Credit Card Validator
Intention d'entrée: Fournissez le contenu source à transformer, valider ou analyser.
Intention de sortie: Recevez une sortie normalisée prête à être copiée, réutilisée ou déboguée.
Entrée d'exemple: 4111 1111 1111 1111
Sortie d'exemple: Valid Visa test number (passes Luhn).

Card number

Valid Visa card number (passes Luhn check).

Digits16

BrandVisa

Formatted4111 1111 1111 1111

Expected check digit0

This tool runs entirely in your browser. Numbers are never sent anywhere.

About the Luhn algorithm

The Luhn algorithm (ISO/IEC 7812-1) is a checksum used by credit cards, IMEI numbers, and some national IDs. Passing the check means the number is internally consistent — it does not mean the card has been issued, is active, or has funds available.

Introduction à l'outil

Vue d'ensemble de l'outil

The Luhn algorithm is the same checksum used by banks, IMEI numbers, and some national IDs. Passing the check means the digits are internally consistent — it does not mean the card has been issued, is active, or has funds. This tool runs entirely in your browser so numbers never leave your device. Use it for test data, QA, and to build intuition about how card numbers are structured.

Cas d'usage

Use Credit Card Validator when you need fast validate credit card numbers with the luhn algorithm, detect the card brand, and compute the expected check digit — 100% client-side.
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Exemples d'entrée/sortie

Intention d'entrée

4111 1111 1111 1111

Intention de sortie

Valid Visa test number (passes Luhn).

Intention d'entrée

5500 0000 0000 0004

Intention de sortie

Valid Mastercard test number (passes Luhn).

Questions fréquentes

Does this check whether the card is real?+

No. It only verifies the structural checksum. Real validation requires a payment gateway.

What brand lookup is used?+

A static table of Issuer Identification Number (IIN) prefixes and valid lengths for Visa, Mastercard, Amex, Discover, JCB, Diners, UnionPay, and Maestro.

Is my card number sent anywhere?+

No. Everything runs entirely client-side. Still, avoid pasting real cards on any site.