PerformanceTiming

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

Warning: This interface is deprecated in the Navigation Timing Level 2 specification. Please use the PerformanceNavigationTiming interface instead.

The PerformanceTiming interface is a legacy interface kept for backwards compatibility and contains properties that offer performance timing information for various events which occur during the loading and use of the current page. You get a PerformanceTiming object describing your page using the window.performance.timing property.

Instance properties

The PerformanceTiming interface doesn't inherit any properties.

These properties each describe the time at which a particular point in the page loading process was reached. Some correspond to DOM events; others describe the time at which internal browser operations of interest took place.

Each time is provided as a number representing the moment, in milliseconds since the UNIX epoch.

These properties are listed in the order in which they occur during the navigation process.

PerformanceTiming.navigationStart Read only Deprecated

When the prompt for unload terminates on the previous document in the same browsing context. If there is no previous document, this value will be the same as PerformanceTiming.fetchStart.

PerformanceTiming.unloadEventStart Read only Deprecated

When the unload event has been thrown, indicating the time at which the previous document in the window began to unload. If there is no previous document, or if the previous document or one of the needed redirects is not of the same origin, the value returned is 0.

PerformanceTiming.unloadEventEnd Read only Deprecated

When the unload event handler finishes. If there is no previous document, or if the previous document, or one of the needed redirects, is not of the same origin, the value returned is 0.

PerformanceTiming.redirectStart Read only Deprecated

When the first HTTP redirect starts. If there is no redirect, or if one of the redirects is not of the same origin, the value returned is 0.

PerformanceTiming.redirectEnd Read only Deprecated

When the last HTTP redirect is completed, that is when the last byte of the HTTP response has been received. If there is no redirect, or if one of the redirects is not of the same origin, the value returned is 0.

PerformanceTiming.fetchStart Read only Deprecated

When the browser is ready to fetch the document using an HTTP request. This moment is before the check to any application cache.

PerformanceTiming.domainLookupStart Read only Deprecated

When the domain lookup starts. If a persistent connection is used, or the information is stored in a cache or a local resource, the value will be the same as PerformanceTiming.fetchStart.

PerformanceTiming.domainLookupEnd Read only Deprecated

When the domain lookup is finished. If a persistent connection is used, or the information is stored in a cache or a local resource, the value will be the same as PerformanceTiming.fetchStart.

PerformanceTiming.connectStart Read only Deprecated

When the request to open a connection is sent to the network. If the transport layer reports an error and the connection establishment is started again, the last connection establishment start time is given. If a persistent connection is used, the value will be the same as PerformanceTiming.fetchStart.

PerformanceTiming.connectEnd Read only Deprecated

When the connection is opened network. If the transport layer reports an error and the connection establishment is started again, the last connection establishment end time is given. If a persistent connection is used, the value will be the same as PerformanceTiming.fetchStart. A connection is considered as opened when all secure connection handshake, or SOCKS authentication, is terminated.

PerformanceTiming.secureConnectionStart Read only Deprecated

When the secure connection handshake starts. If no such connection is requested, it returns 0.

PerformanceTiming.requestStart Read only Deprecated

When the browser sent the request to obtain the actual document, from the server or from a cache. If the transport layer fails after the start of the request and the connection is reopened, this property will be set to the time corresponding to the new request.

PerformanceTiming.responseStart Read only Deprecated

When the browser received the first byte of the response, from the server from a cache, or from a local resource.

PerformanceTiming.responseEnd Read only Deprecated

When the browser received the last byte of the response, or when the connection is closed if this happened first, from the server, the cache, or from a local resource.

PerformanceTiming.domLoading Read only Deprecated

When the parser started its work, that is when its Document.readyState changes to 'loading' and the corresponding readystatechange event is thrown.

PerformanceTiming.domInteractive Read only Deprecated

When the parser finished its work on the main document, that is when its Document.readyState changes to 'interactive' and the corresponding readystatechange event is thrown.

PerformanceTiming.domContentLoadedEventStart Read only Deprecated

Right before the parser sent the DOMContentLoaded event, that is right after all the scripts that need to be executed right after parsing have been executed.

PerformanceTiming.domContentLoadedEventEnd Read only Deprecated

Right after all the scripts that need to be executed as soon as possible, in order or not, have been executed.

PerformanceTiming.domComplete Read only Deprecated

When the parser finished its work on the main document, that is when its Document.readyState changes to 'complete' and the corresponding readystatechange event is thrown.

PerformanceTiming.loadEventStart Read only Deprecated

When the load event was sent for the current document. If this event has not yet been sent, it returns 0.

PerformanceTiming.loadEventEnd Read only Deprecated

When the load event handler terminated, that is when the load event is completed. If this event has not yet been sent, or is not yet completed, it returns 0.

Instance methods

The PerformanceTiming interface doesn't inherit any methods.

PerformanceTiming.toJSON() Deprecated

Returns a JSON object representing this PerformanceTiming object.

Specifications

Specification
Navigation Timing Level 2
# dom-performancetiming

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
PerformanceTiming
Deprecated
connectEnd
Deprecated
connectStart
Deprecated
domComplete
Deprecated
domContentLoadedEventEnd
Deprecated
domContentLoadedEventStart
Deprecated
domInteractive
Deprecated
domLoading
Deprecated
domainLookupEnd
Deprecated
domainLookupStart
Deprecated
fetchStart
Deprecated
loadEventEnd
Deprecated
loadEventStart
Deprecated
navigationStart
Deprecated
redirectEnd
Deprecated
redirectStart
Deprecated
requestStart
Deprecated
responseEnd
Deprecated
responseStart
Deprecated
secureConnectionStart
Deprecated
toJSON
Deprecated
unloadEventEnd
Deprecated
unloadEventStart
Deprecated

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
Deprecated. Not for use in new websites.

See also