What is TX in PayPal?

PayPal, a leading online payment system, facilitates transactions by securely transmitting crucial details to merchants. One such detail is the transaction ID (tx), which uniquely identifies each payment made through the platform.

During the payment process, PayPal leverages the HTTP protocol to send this transaction ID as a GET variable. This method ensures that the information is appended to the URL and can be easily accessed by the recipient's server.

The transmission of the transaction ID occurs when the payment is successfully processed and confirmed by PayPal. It is a crucial step in the payment workflow, as it allows merchants to verify and track payments.

Merchants are required to specify a Return URL in their PayPal account profile. This URL serves as the destination where PayPal redirects users after completing the payment process.

When PayPal sends the transaction ID as a GET variable, it does so by appending it to the Return URL. This enables the merchant's server to access and process the transaction ID upon the user's return.