PerformanceResourceTiming.encodedBodySize

The encodedBodySize read-only property represents the size (in octets) received from the fetch (HTTP or cache), of the payload body, before removing any applied content-codings.

Note: This feature is available in Web Workers.

If the resource is retrieved from an application cache or a local resource, it must return the size of the payload body before removing any applied content-codings.

Syntax

resource.encodedBodySize;

Return value

A number representing the size (in octets) received from the fetch (HTTP or cache), of the payload body, before 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 PerformanceEntry.*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

Specification Status Comment
Resource Timing Level 1
The definition of 'encodedBodySize' in that specification.
Candidate Recommendation Initial definition.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support54 No No No41 No
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support5454 No No41 No6.0

Document Tags and Contributors

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