Methods and devices include a server and at least two web browsers operable on at least two different computing devices. Each browser reports results of processing and rendering of webpages to the server. The server aggregates the data. The server generates metadata from the aggregated browsers. The server transmits the generated metadata to at least one computing device. The computing device renders a webpage using at least a portion of the provided metadata. The metadata may identify portions of JavaScript that can be processed in parallel. The metadata may identify a library portion that does not have to be loaded. The metadata may identify a portion of the webpage that may be rendered first before a second portion of the webpage. Returning metadata to the computing device can assist the computing device in parsing, analyzing or executing the request for the webpage.