Credit card security code is the security code of credit card for online or telephone transactions. Generally, it is a 3-or 4-digit number printed on the back of a credit card, and the printing position of different types of cards will be different.

Turn the credit card over. There are several digits on the cardholder's signature, and the last three digits are the credit card security code.

Credit card security code is the security code of credit card for online or telephone transactions. Generally, it is a 3-or 4-digit number printed on the back of a credit card, and the printing position of different types of cards will be different. Turn the credit card over. There are several digits on the cardholder's signature, and the last three digits are the credit card security code. Credit card security code is usually used to prove that the payer has a credit card at the time of transaction to prevent credit card fraud.

Extended data:

CCB's credit card security code shows 7 digits, of which the first 4 digits are the last 4 digits of the credit card number, and the last 3 digits are the security check code of the credit card. If you need a credit card security code, just enter the last 3 digits.

The generation method of credit card security code is that the bank extracts the account number, validity period and service code of the card, arranges them and then calculates them through a series of complicated algorithms. After this set of numbers is generated, only the issuing bank and the holder of the bank card know what this number is.

References:

Baidu encyclopedia-credit card security code