PerformanceNavigationTiming.loadEventStart

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The loadEventStart read-only property returns a timestamp representing the time value equal to the time immediately before the load event of the current document is fired.

Syntax

perfEntry.loadEventStart;

Return Value

A timestamp representing a time value equal to the time immediately before the load event of the current document is fired.

Example

The following example illustrates this property's usage.

function print_nav_timing_data() {
  // Use getEntriesByType() to just get the "navigation" events
  var perfEntries = performance.getEntriesByType("navigation");

  for (var i=0; i < perfEntries.length; i++) {
    console.log("= Navigation entry[" + i + "]");
    var p = perfEntries[i];
    // dom Properties
    console.log("DOM content loaded = " + (p.domContentLoadedEventEnd - p.domContentLoadedEventStart));
    console.log("DOM complete = " + p.domComplete);
    console.log("DOM interactive = " + p.interactive);
 
    // document load and unload time
    console.log("document load = " + (p.loadEventEnd - p.loadEventStart));
    console.log("document unload = " + (p.unloadEventEnd - p.unloadEventStart));
    
    // other properties
    console.log("type = " + p.type);
    console.log("redirectCount = " + p.redirectCount);
  }
}

Specifications

Specification Status Comment
Navigation Timing Level 2
The definition of 'loadEventStart' in that specification.
Working Draft Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic support
Experimental
Chrome Full support 57Edge Full support YesFirefox Full support 58IE No support NoOpera Full support 44Safari No support NoWebView Android Full support 57Chrome Android Full support 57Edge Mobile Full support YesFirefox Android Full support 58Opera Android Full support 44Safari iOS No support NoSamsung Internet Android Full support 7.0

Legend

Full support  
Full support
No support  
No support
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.

Document Tags and Contributors

Contributors to this page: fscholz, chrisdavidmills, jpmedley, rolfedh, AFBarstow
Last updated by: fscholz,