A system for monitoring the status of digital certificates is provided. The system includes a responder computer device. The responder computer device is programmed to store, in a database, a plurality of statuses associated with a plurality of digital certificates. The responder computer device is further programmed to receive, from a first computer device, a request message including an identifier of a target certificate. The responder computer device is further programmed to query the database to retrieve status information about the target certificate, generate a response message based on the retrieved status information, and transmit the response message to the first computer device.