The PIX Key is a form of identification for a bank account, like a nickname.
Before the launch of PIX in Brazil, whenever a bank transfer needed to be made, it was necessary to provide bank details such as Bank, Account, Bank Branch, and Digit. These details functioned as the address where the funds should be transferred to. With the arrival of PIX, the concept of the PIX Key was created, which is also a bank detail but in a summarized form. The PIX key can be the CPF or CNPJ (Brazilian taxpayer identification numbers), email address, cell phone number, or even a random key. The PIX Key will always be linked to a bank account, so it is also possible to make a payment via PIX using bank details.