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Credit Card Number Validator

Check a card number’s format: Luhn checksum, length and network (Visa, Mastercard, Amex…).

Tool inputs stay in your browser · optional AI search sends your query

Good to know: Checks the format only: Luhn checksum, length and the network’s number range. It cannot tell whether a card is real, active or has funds, and nothing is sent anywhere.

How to use it (step by step)

  1. 1Fill in the boxes: “Card number”. Example numbers are already there so you can see how it works; replace them with yours.
  2. 2The result updates instantly as you type (on a phone it is below the boxes).
  3. 3The bold line is the main answer. Tap Copy next to any value to copy it.

Words to know

Luhn check
A quick math test every real card number passes, like a spelling check for numbers. Passing it only means the number is typed in the right shape, not that the card is real.
Hash / fingerprint (SHA-256)
A short code calculated from a file or text. Change even one letter and the code becomes completely different, so it proves nothing was altered.
Page range
A way to choose pages: 1-3 means pages 1 to 3; 5 means only page 5; 7- means page 7 to the end.

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