The PerformanceNavigationTiming interface provides methods and properties to store and retrieve metrics regarding the browser's document navigation events. For example, this interface can be used to determine how much time it takes to load or unload a document.

Only the current document is included in the performance timeline, so there is only one PerformanceNavigationTiming object in the performance timeline. It inherits all of the properties and methods of PerformanceResourceTiming and PerformanceEntry.

The following diagram shows all of the timestamp properties defined in PerformanceNavigationTiming.

This interface extends the following PerformanceEntry properties by qualifying and constraining them as follows:

PerformanceEntry.entryType Read only

Returns "navigation".

PerformanceEntry.name Read only

Returns the document's URL.

PerformanceEntry.startTime Read only

Returns a DOMHighResTimeStamp with a value of "0".

PerformanceEntry.duration Read only

Returns a timestamp that is the difference between the PerformanceNavigationTiming.loadEventEnd and PerformanceEntry.startTime properties.

This interface also extends the following PerformanceResourceTiming properties by qualifying and constraining them as follows:

PerformanceResourceTiming.initiatorType Read only

Returns "navigation".

The interface also supports the following properties:

PerformanceNavigationTiming.activationStart Read only Experimental

A DOMHighResTimeStamp representing the time between when a document starts prerendering and when it is activated.

PerformanceNavigationTiming.domComplete Read only

A DOMHighResTimeStamp representing the time immediately before the user agent sets the document's readyState to "complete".

PerformanceNavigationTiming.domContentLoadedEventEnd Read only

A DOMHighResTimeStamp representing the time immediately after the current document's DOMContentLoaded event handler completes.

PerformanceNavigationTiming.domContentLoadedEventStart Read only

A DOMHighResTimeStamp representing the time immediately before the current document's DOMContentLoaded event handler starts.

PerformanceNavigationTiming.domInteractive Read only

A DOMHighResTimeStamp representing the time immediately before the user agent sets the document's readyState to "interactive".

PerformanceNavigationTiming.loadEventEnd Read only

A DOMHighResTimeStamp representing the time immediately after the current document's load event handler completes.

PerformanceNavigationTiming.loadEventStart Read only

A DOMHighResTimeStamp representing the time immediately before the current document's load event handler starts.

PerformanceNavigationTiming.redirectCount Read only

A number representing the number of redirects since the last non-redirect navigation in the current browsing context.

PerformanceNavigationTiming.type Read only

A string representing the navigation type. Either "navigate", "reload", "back_forward" or "prerender".

PerformanceNavigationTiming.unloadEventEnd Read only

A DOMHighResTimeStamp representing the time immediately after the current document's unload event handler completes.

PerformanceNavigationTiming.unloadEventStart Read only

A DOMHighResTimeStamp representing the time immediately before the current document's unload event handler starts.

PerformanceNavigationTiming.toJSON()

Returns a JSON representation of the PerformanceNavigationTiming object.

• Performance.navigation
• PerformanceNavigation