2025
2 featuresAn event or first-input performance entry measures the latency of user input events, such as mouse clicks or keypresses. They're used to calculate interaction to next paint (INP), a common metric for perceived responsiveness.
A largest-contentful-paint performance entry measures the time it takes for the largest image or text to appear. Largest contentful paint (LCP) is a common metric for perceived loading times.
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.
Limited Availability
11 featuresAn interaction-contentful-paint performance entry measures the duration of an interaction that causes one or more contentful paints. You can use it to measure LCP for soft navigations in single page apps.
The notRestoredReasons property of a PerformanceNavigationTiming object explains why the current document was blocked from using the back/forward cache (also known as the bfcache) on navigation.
A long-animation-frame performance entry measures rendering updates that take longer than 50 milliseconds. Also known as LoAFs.
A visibility-state performance entry measures the timing of page visibility state changes, such as when a tab is no longer visible or the user has switched to another app.
The window.performance.timing and window.performance.navigation APIs report performance timing information for events that occur during the loading and use of the current page.
The measureUserAgentSpecificMemory() method estimates the memory usage of a web application including all its iframes and workers.
A layout-shift performance entry measures the layout stability of web pages based on movements of the elements on the page. They're used to calculate cumulative layout shift (CLS), a common metric for perceived stability.
An element performance entry measures the time to render elements that have the elementtiming attribute.
A longtask performance entry measures tasks that occupy the UI thread for 50 milliseconds or more, a metric for input latency, delayed animations, and other sources of "jank."
A container performance entry measures time to render child elements, for container elements that have the containertiming attribute.