1. A computer-implemented method for testing an opt-out system associated with at least one advertising system that uses cookies, the method comprising: transmitting, by a test system, a first request to an opt-out system, wherein the first request corresponds to a first test for testing the opt-out system; receiving, by the test system, a first stream sent from the opt-out system in response to the first request; determining a first outcome of the first test by analyzing contents of the first stream; transmitting, by the test system, a second request to an opt-out system, wherein the second request corresponds to a second test for testing an advertising system that uses cookies; receiving, by the test system, an opt-out cookie sent from the advertising system; determining a second outcome of the second test by analyzing a value associated with the opt-out cookie; and generating a report based on at least one of the first outcome and the second outcome.