Body.json

The json() method of the Body mixin takes a Response stream and reads it to completion. It returns a promise that resolves with an object literal containing the JSON data.

Syntax

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

Parameters

None.

Returns

A promise that resolves with an object literal containing the JSON data.

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 our JSON out of the response using json(), then read values out of the JSON 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(json) {
    for(i = 0; i < json.products.length; i++) {
      var listItem = document.createElement('li');
      listItem.innerHTML = '<strong>' + json.products[i].Name + '</strong> can be found in ' + json.products[i].Location + '. Cost: <strong>£' + json.products[i].Price + '</strong>';
      myList.appendChild(listItem);
    }
  });

Specifications

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

Browser compatibility

[1] Behind a preference in version 41.

[2] Behind a preference starting with version 34.

[3] Behind a preference in version 28.

See also

• ServiceWorker API
• HTTP access control (CORS)
• HTTP