Systems and methods for a cross-site opt-in network

A computing system for tracking a user across multiple web site domains over a computerized network, the system comprising:

• one or more hardware computer processors;
• and
• one or more storage devices configured to store software instructions executable by the one or more hardware computer processors to cause the computing system to:
• send a first first-party user identifier to a collector in response to a user accessing a first website;
• generate a first user prompt in response to the user accessing the first website;
• receive a first input from the user in response to the first user prompt;
• redirect the user to a centralized domain;
• send a second first-party user identifier associated with the user and the centralized domain to the collector;
• correlate the first first-party user identifier with the second first-party user identifier to determine that the user is associated with both the first first-party user identifier and the second first-party user identifier;
• and
• display a webpage of the centralized domain or a landing page in response to the correlation,
• wherein the one or more storage devices are further configured to store software instructions executable by the one or more hardware computer processors to cause the computing system to determine by the collector whether there is an active user having an ability to opt into the computerized network via a user prompt by sending one or more requests to the collector at predetermined intervals of time.