Card
Validator.
Paste a card number to check it against the Luhn algorithm and identify the brand from its BIN prefix. Nothing leaves your browser — this is structural validation only, not a real funds check.
Card NumberSpaces and dashes are ignored
UNKNOWN
•••• •••• •••• ••••
CARD HOLDERYOUR NAME
VALID THRUMM/YY
Verdict—
—
Type at least 12 digits to validate
The Luhn algorithm
Starting from the rightmost digit and moving left, double every second digit. If doubling produces a number greater than 9, subtract 9. Sum all the digits. If the total is a multiple of 10, the number passes Luhn.
4 5 3 9 1 4 8 8 0 3 4 3 6 4 6 7
↑ ↑ ↑ ↑ ↑ ↑ ↑ ↑
(every other digit doubled, then summed mod 10)
What this proves. Luhn is a checksum, not authentication — it catches single-digit typos and most transpositions, but a number that passes Luhn isn't necessarily issued, active, or yours to charge.