The Web Timing Specification (draft) aims at providing a standard set of APIs which allow for true end-to-end instrumentation of page load times across browsers.
To quote the w3 spec: “This specification (Web Timing Specification) defines an interface for web applications to access timing information related to navigation and elements.” The API is based on the Navigation Timing and Resource Timing interfaces, respectively.
While I haven’t seen this specification mentioned as part of the HTML5 Family before, in many ways I would consider it to be a worthy candidate for membership as it provides a standards based API through which web applications can be tested for load efficiency. This is obviously something quite useful for any web application as, the ability to precisely measure page load times – and implement optimizations as needed – affords developers the opportunity to provide an improved user experience.
Historically, the ability to accurately measure page load times of web applications has been quite challenging for a number reasons. Just knowing when and where to begin is debatable and, determining the best means of doing so can be a challenge in of itself. Regardless of any current strategies being used, the result is never entirely accurate. With Web Timing developers need not be concerned with these specifics as the API provides the ability to truly measure page load times by encompassing the full scope of loading and parsing a page. This includes the time involved to request, receive and render an HTML document.