The json() method of the Body mixin takes a Response stream and reads it to completion. It returns a promise that resolves with the result of parsing the body text as JSON.

Syntax

response.json().then(function(data) {
  // do something with your data
});

Parameters

None.

Returns

A promise that resolves with the result of parsing the body text as JSON. This could be anything that can be represented by JSON — an object, an array, a string, a number...

Example

In our fetch json example (run fetch json live), we create a new request using the Request.Request constructor, then use it to fetch a .json file. When the fetch is successful, we read and parse the data using json(), then read values out of the resulting objects as you'd expect and insert them into list items to display our product data.

var myList = document.querySelector('ul');

var myRequest = new Request('products.json');

fetch(myRequest)
  .then(function(response) { return response.json(); })
  .then(function(data) {
    for (var i = 0; i < data.products.length; i++) {
      var listItem = document.createElement('li');
      listItem.innerHTML = '<strong>' + data.products[i].Name + '</strong> can be found in ' +
                           data.products[i].Location +
                           '. Cost: <strong>£' + data.products[i].Price + '</strong>';
      myList.appendChild(listItem);
    }
  });

Specifications

Specification Status Comment
Fetch
The definition of 'json()' in that specification.
Living Standard  

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support

42

411

Yes

39

342

No

29

283

No
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support No No Yes No No No No

1. From version 41: this feature is behind the Experimental Web Platform Features preference. To change preferences in Chrome, visit chrome://flags.

2. From version 34: this feature is behind the dom.fetch.enabled preference. To change preferences in Firefox, visit about:config.

3. From version 28: this feature is behind the Experimental Web Platform Features preference.

See also

Document Tags and Contributors

 Last updated by: fscholz,