A method for determining a display time of a page is provided, including the following method operations: receiving a request for page data from a client; in response to the request, sending the page data to the client, the page data defining a page when rendered by the client, the rendered page including a page event module configured to detect and log events in a beacon for transmission, the events being selected from a group comprising a page unhide event, a page hide event, and a page unload event; receiving the beacon from the client; reading events logged in the beacon; and determining a display time of the page based on the events logged in the beacon.