PerformanceNavigationTiming: toJSON() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since October 2021.

The toJSON() method of the PerformanceNavigationTiming interface is a serializer; it returns a JSON representation of the PerformanceNavigationTiming object.

Syntax

js
toJSON()

Parameters

None.

Return value

A JSON object that is the serialization of the PerformanceNavigationTiming object.

Examples

Using the toJSON method

In this example, calling entry.toJSON() returns a JSON representation of the PerformanceNavigationTiming object.

js
const observer = new PerformanceObserver((list) => {
  list.getEntries().forEach((entry) => {
    console.log(entry.toJSON());
  });
});

observer.observe({ entryTypes: ["navigation"] });

This would log a JSON object like so:

json
{
  "name": "https://en.wikipedia.org/wiki/Main_Page",
  "entryType": "navigation",
  "startTime": 0,
  "duration": 227.60000002384186,
  "initiatorType": "navigation",
  "nextHopProtocol": "h2",
  "renderBlockingStatus": "blocking",
  "workerStart": 0,
  "redirectStart": 4,
  "redirectEnd": 71.40000000596046,
  "fetchStart": 71.40000000596046,
  "domainLookupStart": 71.40000000596046,
  "domainLookupEnd": 71.40000000596046,
  "connectStart": 71.40000000596046,
  "connectEnd": 71.40000000596046,
  "secureConnectionStart": 71.40000000596046,
  "requestStart": 73.7000000178814,
  "responseStart": 102.90000000596046,
  "responseEnd": 105.2000000178814,
  "transferSize": 19464,
  "encodedBodySize": 19164,
  "decodedBodySize": 83352,
  "serverTiming": [
    {
      "name": "cache",
      "duration": 0,
      "description": "hit-front"
    },
    {
      "name": "host",
      "duration": 0,
      "description": "cp3062"
    }
  ],
  "unloadEventStart": 0,
  "unloadEventEnd": 0,
  "domInteractive": 178.10000002384186,
  "domContentLoadedEventStart": 178.2000000178814,
  "domContentLoadedEventEnd": 178.2000000178814,
  "domComplete": 227.60000002384186,
  "loadEventStart": 227.60000002384186,
  "loadEventEnd": 227.60000002384186,
  "type": "navigate",
  "redirectCount": 1,
  "activationStart": 0
}

To get a JSON string, you can use JSON.stringify(entry) directly; it will call toJSON() automatically.

Specifications

Specification
Navigation Timing Level 2
# dom-performancenavigationtiming-tojson

Browser compatibility

BCD tables only load in the browser

See also