The Performance interface provides access to performance-related information for the current page. It's part of the High Resolution Time API, but is enhanced by the Performance Timeline API, the Navigation Timing API, the User Timing API, and the Resource Timing API.

An object of this type can be obtained by calling the Window.performance read-only attribute.

Note: This interface and its members are available in Web Workers, except where indicated below. Also note that performance markers and measures are per context. If you create a mark on the main thread (or other worker), you cannot see it in a worker thread, and vice versa.

Properties

The Performance interface doesn't inherit any properties.

Performance.navigation Read only Not available to workers
A PerformanceNavigation object that provides useful context about the operations included in the times listed in timing, including whether the page was a load or a refresh, how many redirections occurred, and so forth.
  Performance.timing Read only Not available to workers
A PerformanceTiming object containing latency-related performance information
performance.memory
A non-standard extension added in Chrome, this property provides an object with basic memory usage information. You should not use this non-standard API.
Performance.timeOrigin Read only  
Returns the high resolution timestamp of the start time of the performance measurement.

Event handlers

Performance.onresourcetimingbufferfull
An EventTarget which is a callback that will be called when the resourcetimingbufferfull event is fired.

Methods

The Performance interface doesn't inherit any methods.

Performance.clearMarks()
Removes the given mark from the browser's performance entry buffer.
Performance.clearMeasures()
Removes the given measure from the browser's performance entry buffer.
Performance.clearResourceTimings()
Removes all performance entries with a entryType of "resource" from the browser's performance data buffer.
Performance.getEntries()
Returns a list of PerformanceEntry objects based on the given filter.
Performance.getEntriesByName()
Returns a list of PerformanceEntry objects based on the given name and entry type.
Performance.getEntriesByType()
Returns a list of PerformanceEntry objects of the given entry type.
Performance.mark()
Creates a timestamp in the browser's performance entry buffer with the given name.
Performance.measure()
Creates a named timestamp in the browser's performance entry buffer between two specified marks (known as the start mark and end mark, respectively).
Performance.now()
Returns a DOMHighResTimeStamp representing the number of milliseconds elapsed since a reference instant.
Performance.setResourceTimingBufferSize()
Sets the browser's resource timing buffer size to the specified number of "resource" type performance entry objects.
Performance.toJSON() Not available to workers
Is a jsonizer returning a json object representing the Performance object.

Specifications

Specification Status Comment
High Resolution Time Level 2
The definition of 'toJSON()' in that specification.
Candidate Recommendation Defines toJson() method.
High Resolution Time
The definition of 'Performance' in that specification.
Recommendation Defines now() method.
Performance Timeline Level 2
The definition of 'Performance extensions' in that specification.
Candidate Recommendation Changes getEntries() interface.
Performance Timeline
The definition of 'Performance extensions' in that specification.
Recommendation Defines getEntries(), getEntriesByType() and getEntriesByName() methods.
Resource Timing Level 1
The definition of 'Performance extensions' in that specification.
Candidate Recommendation Defines clearResourceTimings() and setResourceTimingBufferSize() methods and the onresourcetimingbufferfull property.
User Timing Level 2
The definition of 'Performance extensions' in that specification.
Working Draft Clarifies mark(), clearMark(), measure() and clearMeasure() methods.
User Timing
The definition of 'Performance extensions' in that specification.
Recommendation Defines mark(), clearMark(), measure() and clearMeasure() methods.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 6Edge Full support YesFirefox Full support 7IE Full support 9Opera Full support 15Safari Full support 8WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 7Opera Android Full support 15Safari iOS Full support 9Samsung Internet Android ?
clearMarksChrome Full support 43Edge Full support YesFirefox Full support 41IE Full support 10Opera Full support 33Safari Full support 11WebView Android Full support 46Chrome Android Full support 46Edge Mobile Full support YesFirefox Android Full support 42Opera Android Full support 33Safari iOS Full support 11Samsung Internet Android ?
clearMeasuresChrome Full support 43Edge Full support YesFirefox Full support 41IE Full support 10Opera Full support 33Safari Full support 11WebView Android Full support 46Chrome Android Full support 46Edge Mobile Full support YesFirefox Android Full support 42Opera Android Full support 33Safari iOS Full support 11Samsung Internet Android ?
clearResourceTimingsChrome Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Full support YesFirefox Full support YesIE Full support YesOpera Full support YesSafari Full support 11WebView Android Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Chrome Android Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Mobile Full support YesFirefox Android Full support YesOpera Android Full support YesSafari iOS Full support 11Samsung Internet Android ?
getEntriesChrome Full support YesEdge Full support YesFirefox Full support YesIE Full support YesOpera No support NoSafari Full support 11WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 25Opera Android No support NoSafari iOS Full support 11Samsung Internet Android ?
getEntriesByNameChrome Full support YesEdge Full support YesFirefox Full support YesIE Full support YesOpera No support NoSafari Full support 11WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 25Opera Android No support NoSafari iOS Full support 11Samsung Internet Android ?
getEntriesByTypeChrome Full support YesEdge Full support YesFirefox Full support YesIE Full support YesOpera No support NoSafari Full support 11WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 25Opera Android No support NoSafari iOS Full support 11Samsung Internet Android ?
markChrome Full support 43Edge Full support YesFirefox Full support 41IE Full support 10Opera Full support 33Safari Full support 11WebView Android Full support 46Chrome Android Full support 46Edge Mobile Full support YesFirefox Android Full support 42Opera Android Full support 33Safari iOS Full support 11Samsung Internet Android ?
measureChrome Full support 43Edge Full support YesFirefox Full support 41IE Full support 10Opera Full support 33Safari Full support 11WebView Android Full support 46Chrome Android Full support 46Edge Mobile Full support YesFirefox Android Full support 42Opera Android Full support 33Safari iOS Full support 11Samsung Internet Android ?
memory
Non-standard
Chrome Full support YesEdge ? Firefox No support NoIE ? Opera Full support YesSafari No support NoWebView Android Full support YesChrome Android Full support YesEdge Mobile ? Firefox Android No support NoOpera Android Full support YesSafari iOS No support NoSamsung Internet Android ?
navigation
Deprecated
Chrome Full support 10Edge Full support YesFirefox Full support 7IE Full support 9Opera Full support 15Safari Full support 8WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 7Opera Android No support NoSafari iOS Full support 9Samsung Internet Android ?
nowChrome Full support 24Edge Full support YesFirefox Full support 15
Notes
Full support 15
Notes
Notes In Firefox 57.0.4 the accuracy was reduced to 20 microseconds.
Notes In Firefox 59 the accuracy was reduced to 2 milliseconds.
IE Full support 10Opera Full support 15Safari Full support 8WebView Android Full support YesChrome Android Full support 25Edge Mobile Full support YesFirefox Android Full support 15
Notes
Full support 15
Notes
Notes In Firefox 57.0.4 the accuracy was reduced to 20 microseconds.
Notes In Firefox 59 the accuracy was reduced to 2 milliseconds.
Opera Android No support NoSafari iOS Full support 9Samsung Internet Android ?
onresourcetimingbufferfullChrome Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge ? Firefox Full support YesIE No support NoOpera No support NoSafari No support NoWebView Android Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Chrome Android Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Mobile ? Firefox Android Full support YesOpera Android Full support YesSafari iOS No support NoSamsung Internet Android ?
setResourceTimingBufferSizeChrome Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Full support YesFirefox Full support YesIE Full support YesOpera Full support YesSafari No support NoWebView Android Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Chrome Android Full support 46
Full support 46
No support ? — 57
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge Mobile Full support YesFirefox Android Full support YesOpera Android Full support YesSafari iOS No support NoSamsung Internet Android ?
timeOrigin
Experimental
Chrome Full support 62Edge ? Firefox Full support 59IE ? Opera Full support 49Safari No support NoWebView Android Full support 62Chrome Android Full support 62Edge Mobile ? Firefox Android Full support 59Opera Android Full support 49Safari iOS No support NoSamsung Internet Android ?
timing
Deprecated
Chrome Full support 6Edge Full support YesFirefox Full support 7IE Full support 9Opera Full support 15Safari Full support 8WebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 7Opera Android Full support 15Safari iOS Full support 9Samsung Internet Android ?
toJSONChrome No support NoEdge Full support YesFirefox Full support 25IE ? Opera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoEdge Mobile Full support YesFirefox Android Full support 25Opera Android No support NoSafari iOS No support NoSamsung Internet Android ?

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.
Deprecated. Not for use in new websites.
See implementation notes.
See implementation notes.
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

Document Tags and Contributors

Last updated by: sideshowbarker,