If you have your credit card with you, you can directly check the security code on the back of the credit card. If you don't have your credit card with you, you can only call the customer service hotline of the card-issuing bank. After verifying your identity, the customer service staff will tell you the credit card security code. However, for security reasons, some banks do not provide manual customer service to query the security code. In this case, you can only use the first method to query the security code.

Credit card security code is relatively important private information. In addition to remembering it yourself, users should not tell others easily.

Credit card security code is a security code for credit cards when conducting online or telephone transactions. It is usually a 3 or 4-digit number printed on the credit card, and the location of the printing will vary on different types of cards. It is often used to prevent credit card fraud by verifying that the payer owned the credit card at the time of the transaction.

The credit card security code is a set of 3 or 4 digits on the credit card. The generation method is that the bank extracts the card account number, validity period, and service code, arranges them, and then calculates them through a series of complex algorithms. After this set of numbers is generated, only the issuing bank and the bank card holder know what the number is.

CVV password verification means that commercial banks add custom algorithm verification codes to the bank card number encoding rules and magnetic stripe data formats they use. The relevant bank cards are also called CVN bank cards. CVV information is stored in the magnetic track of the magnetic stripe bank card. Based on the card number, track master account number, card-issuing bank logo code and other information, it is encrypted through a special encryption algorithm customized by each bank. Each step is encrypted using CVKA technology to obtain the verification code. .

Because the encryption algorithms of different banks are different, some counterfeit cards illegally produced using the obtained bank card information can be identified and cannot be used when the card issuer decrypts them.

The security code of the VISA card is called CVV2 (Card Verification Value 2), which is a 3-digit number and is printed flat on the signature line on the back of the credit card at the last 4 digits of the card number.

The security code of MasterCard is called CVC2 (Card Validation Code 2). It has 3 digits and is printed flat on the signature line on the back of the credit card after the 4 digits of the card number.

The security code of the Discover Card is called Cardmember ID, which is a 3-digit number and is printed flat on the signature line on the back of the credit card.

The security code of American Express is called CID (Card Identification Number), which is a 4-digit number and is printed flat on the front of the credit card above the credit card number.

The security code of China UnionPay is called CVN2 (Card Validation Number 2). It has 3 digits and is printed flat on the signature line on the back of the credit card after the last 4 digits of the card number.

The security code of JCB card (Japan Credit Bureau) is called CAV2 (Card Authentication Value 2). It has 3 digits and is printed flat on the signature line on the back of the credit card after the 4 digits of the card number.