PerformanceResourceTiming.decodedBodySize

The decodedBodySize read-only property returns the size (in octets) received from the fetch (HTTP or cache) of the message body, after removing any applied content-codings. If the resource is retrieved from an application cache or local resources, it returns the size of the payload after removing any applied content-codings.

Note: This feature is available in Web Workers

Syntax

resource.decodedBodySize;

Return value

The size (in octets) received from the fetch (HTTP or cache) of the message body, after removing any applied content-codings.

Example

The following example, the value of the size properties of all "resource" type events are logged.

function log_sizes(perfEntry){
  // Check for support of the *size properties and print their values
  // if supported.
  if ("decodedBodySize" in perfEntry)
    console.log("decodedBodySize = " + perfEntry.decodedBodySize);
  else
    console.log("decodedBodySize = NOT supported");

  if ("encodedBodySize" in perfEntry)
    console.log("encodedBodySize = " + perfEntry.encodedBodySize);
  else
    console.log("encodedBodySize = NOT supported");

  if ("transferSize" in perfEntry)
    console.log("transferSize = " + perfEntry.transferSize);
  else
    console.log("transferSize = NOT supported");
}
function check_PerformanceEntries() {
  // Use getEntriesByType() to just get the "resource" events
  var p = performance.getEntriesByType("resource");
  for (var i=0; i < p.length; i++) {
    log_sizes(p[i]);
  }
}

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
decodedBodySize
54
17
45
No
41
No
54
54
45
41
No
6.0

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https://developer.mozilla.org/en-US/docs/Web/API/PerformanceResourceTiming/decodedBodySize