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Credit Card Number Validator
Check whether a card number's digits pass the Luhn checksum, see its likely brand, and generate Luhn-valid test numbers for building and testing checkout forms.
How it works
See the Luhn result
The tool runs the standard Luhn checksum and flags whether the digits form a mathematically valid number.
Generate test numbers
Need sample data instead? Pick a brand and generate a fresh Luhn-valid number for your test suite.
FAQ
Does this check if a card is real or active?
No. It only verifies that the number's digits satisfy the Luhn checksum used by all major card networks to catch typos. It cannot tell you whether a card exists, is active, or is authorized for a charge.
What is the Luhn algorithm?
A simple checksum formula that doubles every second digit from the right, sums the digits, and checks that the total is a multiple of 10. It's designed to catch common data-entry mistakes, not fraud.
Are the generated test numbers real cards?
No. They are randomly generated numbers that satisfy the Luhn checksum and a brand's prefix pattern, intended only for testing checkout form validation logic — the same idea used by payment providers' published sandbox test cards.