2023
2 featuresThe decodedBodySize, encodedBodySize, and transferSize properties of the PerformanceResourceTiming API reports the size of resources loaded.
The serverTiming property of a resource performance entry contains server timing information about network requests.
2021
2 featuresA paint performance entry measures the duration of "paint" (also called "render") operations as a page loads. It measures the time to First Paint (FP) and First Contentful Paint (FCP), common metrics for perceived loading times.
2017
1 featuresA resource performance entry records when a network event happens while loading a resource, such as when a connection starts and ends. You can use this information to measure loading times.
2015
1 featuresThe performance global object and the PerformanceObserver API provide access to performance-related information for the current execution context.