1, CCB: the card number of savings card is 16 digits or 19 digits, and that of credit card is 16 digits;

2. Agricultural Bank of China: savings card number 19 digits, credit card number 16 digits;

3. ICBC: savings card number 19 digits, credit card number 16 digits;

4. Transportation: the card number of the savings card is 17 digits, and that of the credit card is 16 digits;

6. People's livelihood: savings card number 16 digits, credit card number 16 digits.

There are three formats of bank card number, 19 digits, 17 digits and 16 digits. The credit card number is 16 digits. China Merchants Bank and China Construction Bank are 16, Bank of Communications is 17, and other banks are 19. The first six digits of the card number represent the identification code of the issuing bank, also called BIN number, and different BIN numbers represent different bank card organizations and card levels. Therefore, not all bank cards have the same number of digits. According to different types of cards, different issuing banks, the number of bank cards is also different.