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PerformanceResourceTiming.responseStart

The responseStart property returns a timestamp immediately after the browser receives the first byte of the response from the server, cache, or local resource.

This property is Read only .

Syntax

resource.responseStart;

Return value

A DOMHighResTimeStamp immediately after the browser receives the first byte of the response from the server.

Example

In the following example, the value of the *Start and *End properties of all "resource" type events are logged.

function print_PerformanceEntries() {
  // Use getEntriesByType() to just get the "resource" events
  var p = performance.getEntriesByType("resource");
  for (var i=0; i < p.length; i++) {
    print_start_and_end_properties(p[i]);
  }
}
function print_start_and_end_properties(perfEntry) {
  // Print timestamps of the PerformanceEntry *start and *end properties 
  properties = ["connectStart", "connectEnd",
                "domainLookupStart", "domainLookupEnd",
                "fetchStart", 
                "redirectStart", "redirectEnd",
                "requestStart", 
                "responseStart", "responseEnd",
                "secureConnectionStart"];

  for (var i=0; i < properties.length; i++) {
    // check each property
    var supported = properties[i] in perfEntry;
    if (supported) {
      var value = perfEntry[properties[i]];
      console.log("... " + properties[i] + " = " + value);
    } else {
      console.log("... " + properties[i] + " = NOT supported");
    }
  }
}

Specifications

Specification Status Comment
Resource Timing
The definition of 'responseStart' in that specification.
Editor's Draft Initial definition.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support. 43 (Yes) 40 10 32 No support
Feature Android Edge Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
Basic support. 4.4 (Yes) 42 ? 10.0 32 No support

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/PerformanceResourceTiming/responseStart