Card Validator
Securely validate payment card numbers and identify issuers using the Luhn algorithm.
About Card Validator
Card numbers carry a check digit calculated with the Luhn formula, which catches most typos and transpositions. Validating tests that arithmetic and identifies the issuing network from the leading digits.
How to use it
- Enter the card number.
- Run the check.
- See whether the format and check digit are consistent.
Worth knowing
This only checks that a number is well formed. It cannot tell you whether a card exists, is active, or has funds — only the issuer knows that. Do not enter real card details you would not want in a browser; use test numbers.
Common questions
- It says valid — is the card real?
- No. A number can pass the Luhn check and belong to no account at all. It is a typo check, nothing more.
- What is it useful for?
- Catching mistyped numbers in a form before they reach a payment processor.