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.
-
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 is0
. 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 is0
. 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 correspondingreadystatechange
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 correspondingreadystatechange
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 correspondingreadystatechange
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 returns0.
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 returns0.
Instance methods
The PerformanceTiming
interface doesn't inherit any methods.
PerformanceTiming.toJSON()
Deprecated-
Returns a JSON object representing this
PerformanceTiming
object.
Specifications
This feature is no longer on track to become a standard, as the Navigation Timing specification has marked it as deprecated.
Use the PerformanceNavigationTiming
interface instead.
Browser compatibility
BCD tables only load in the browser
See also
- The
Performance.timing
property that creates such an object. PerformanceNavigationTiming
(part of Navigation Timing Level 2) that has superseded this API.