Systems for credential evaluation and control are provided. In some examples, a request to access data via a website may be received. The request may include a username. A browser extension embedded in the web browser used to request the data via the website may be triggered and one or more credential evaluation functions may be executed. An event record associated with the request to access data may be generated. The event record may be analyzed to determine a designation associated with the website and a designation associated with user credentials provided with the request to access the data. The designation of the website and the designation of the credentials may be compared to determine whether the designations match. If so, access to the requested data may be provided. If not, one or more mitigating actions may be identified and executed.