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

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

Browser compatibility

BCD tables only load in the browser