PayCheck Format Validator

Paste your list and check number length, Luhn checksum and expiration format locally. This does not verify card activity, funds or CVV and does not contact banks.

One number per line, optionally number|MM|YYYY. A fourth field is ignored and never displayed or exported. Results show only the last four digits. Input is cleared when checks start; nothing is saved by this tool. Format Valid does not mean an active card.