PerformanceServerTiming

Note: This feature is available in Web Workers.

Secure context
This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The PerformanceServerTiming interface surfaces server metrics that are sent with the response in the Server-Timing HTTP header.

This interface is restricted to the same origin, but you can use the Timing-Allow-Origin header to specify the domains that are allowed to access the server metrics. Note that this interface is only available in secure contexts (HTTPS) in some browsers.

Properties

PerformanceServerTiming.descriptionRead only
A DOMString value of the server-specified metric description, or an empty string.
PerformanceServerTiming.durationRead only
A double that contains the server-specified metric duration, or value 0.0.
PerformanceServerTiming.nameRead only
A DOMString value of the server-specified metric name.

Methods

PerformanceServerTiming.toJSON
Returns a DOMString that is the JSON representation of the PerformanceServerTiming object.

Example

Given a server that sends the Server-Timing header, for example a node.js server like this:

const http = require('http');

function requestHandler(request, response) {
  const headers = {
    'Server-Timing': `
      cache;desc="Cache Read";dur=23.2,
      db;dur=53,
      app;dur=47.2
    `.replace(/\n/g, '')
  };
  response.writeHead(200, headers);
  response.write('');
  return setTimeout(_ => {
   response.end();
 }, 1000)
};

http.createServer(requestHandler).listen(3000).on('error', console.error);

The PerformanceServerTiming entries are now observable from JavaScript via the PerformanceResourceTiming.serverTiming property:

let entries = performance.getEntriesByType('resource');
console.log(entries[0].serverTiming);
// 0: PerformanceServerTiming {name: "cache", duration: 23.2, description: "Cache Read"}
// 1: PerformanceServerTiming {name: "db", duration: 53, description: ""}
// 2: PerformanceServerTiming {name: "app", duration: 47.2, description: ""}

Specifications

Specification Status Comment
Server Timing
The definition of 'PerformanceServerTiming' in that specification.
Working Draft Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support 65Edge ? Firefox Full support 61IE No support NoOpera Full support 52Safari ? WebView Android Full support 65Chrome Android Full support 65Edge Mobile ? Firefox Android Full support 61Opera Android Full support 52Safari iOS ? Samsung Internet Android ?
description
Experimental
Chrome Full support 65Edge ? Firefox Full support 61IE No support NoOpera Full support 52Safari ? WebView Android Full support 65Chrome Android Full support 65Edge Mobile ? Firefox Android Full support 61Opera Android Full support 52Safari iOS ? Samsung Internet Android ?
duration
Experimental
Chrome Full support 65Edge ? Firefox Full support 61IE No support NoOpera Full support 52Safari ? WebView Android Full support 65Chrome Android Full support 65Edge Mobile ? Firefox Android Full support 61Opera Android Full support 52Safari iOS ? Samsung Internet Android ?
name
Experimental
Chrome Full support 65Edge ? Firefox Full support 61IE No support NoOpera Full support 52Safari ? WebView Android Full support 65Chrome Android Full support 65Edge Mobile ? Firefox Android Full support 61Opera Android Full support 52Safari iOS ? Samsung Internet Android ?
toJSON
Experimental
Chrome Full support 65Edge ? Firefox Full support 61IE No support NoOpera Full support 52Safari ? WebView Android Full support 65Chrome Android Full support 65Edge Mobile ? Firefox Android Full support 61Opera Android Full support 52Safari iOS ? Samsung Internet Android ?

Legend

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

See also

Document Tags and Contributors

Contributors to this page: fscholz
Last updated by: fscholz,