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 the result of parsing the body text as JSON.

Syntax

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

Parameters

None.

Return value

A Promise that resolves to a JavaScript object. This object 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() 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.

const myList = document.querySelector('ul');
const myRequest = new Request('products.json');

fetch(myRequest)
  .then(response => response.json())
  .then(data => {
    for (const product of data.products) {
      let listItem = document.createElement('li');
      listItem.appendChild(
        document.createElement('strong')
      ).textContent = product.Name;
      listItem.append(
        ` can be found in ${
          product.Location
        }. Cost: `
      );
      listItem.appendChild(
        document.createElement('strong')
      ).textContent = `£${product.Price}`;
      myList.appendChild(listItem);
    }
  })
  .catch(console.error);

Specifications

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

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
json
Experimental
Chrome Full support 42
Full support 42
Full support 41
Disabled
Disabled From version 41: this feature is behind the Experimental Web Platform Features preference. To change preferences in Chrome, visit chrome://flags.
Edge Full support ≤18Firefox Full support 39
Full support 39
Full support 34
Disabled
Disabled From version 34: this feature is behind the dom.fetch.enabled preference. To change preferences in Firefox, visit about:config.
IE No support NoOpera Full support 29
Full support 29
Full support 28
Disabled
Disabled From version 28: this feature is behind the Experimental Web Platform Features preference.
Safari Full support 10WebView Android No support NoChrome Android Full support 42Firefox Android No support NoOpera Android Full support 29
Full support 29
Full support 28
Disabled
Disabled From version 28: this feature is behind the Experimental Web Platform Features preference.
Safari iOS Full support 10Samsung Internet Android No support No

Legend

Full support
Full support
No support
No support
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
User must explicitly enable this feature.
User must explicitly enable this feature.

See also