Check whether a card number, IMEI, or similar identifier passes the Luhn checksum. Validation runs in your browser only.
How it works
The Luhn algorithm is a checksum used for card numbers, IMEIs, and other identifiers. It does not confirm that a number is active or real. It only checks whether the digits fit the expected pattern.
Starting from the right, double every second digit.
If a doubled value is greater than 9, subtract 9 from it.
Add all digits together.
If the total is divisible by 10, the number passes the check.