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/Web APIs

Response

The Response interface of the Fetch API represents the response to a request.

You can create a new Response object using the Response() constructor, but you are more likely to encounter a Response object being returned as the result of another API operation—for example, a service worker FetchEvent.respondWith, or a simple fetch().

Constructor

Response()

Creates a new Response object.

Properties

Response.body Read only

A ReadableStream of the body contents.

Response.bodyUsed Read only

Stores a boolean value that declares whether the body has been used in a response yet.

Response.headers Read only

The Headers object associated with the response.

Response.ok Read only

A boolean indicating whether the response was successful (status in the range 200299) or not.

Response.redirected Read only

Indicates whether or not the response is the result of a redirect (that is, its URL list has more than one entry).

Response.status Read only

The status code of the response. (This will be 200 for a success).

Response.statusText Read only

The status message corresponding to the status code. (e.g., OK for 200).

Response.trailers

A Promise resolving to a Headers object, associated with the response with Response.headers for values of the HTTP Trailer header.

Response.type Read only

The type of the response (e.g., basic, cors).

Response.url Read only

The URL of the response.

Methods

Response.arrayBuffer()

Returns a promise that resolves with an ArrayBuffer representation of the response body.

Response.blob()

Returns a promise that resolves with a Blob representation of the response body.

Response.clone()

Creates a clone of a Response object.

Response.error()

Returns a new Response object associated with a network error.

Response.formData()

Returns a promise that resolves with a FormData representation of the response body.

Response.json()

Returns a promise that resolves with the result of parsing the response body text as JSON.

Response.redirect()

Creates a new response with a different URL.

Response.text()

Returns a promise that resolves with a text representation of the response body.

Examples

Fetching an image

In our basic fetch example (run example live) we use a simple fetch() call to grab an image and display it in an <img> element. The fetch() call returns a promise, which resolves to the Response object associated with the resource fetch operation.

You'll notice that since we are requesting an image, we need to run Response.blob to give the response its correct MIME type.

const image = document.querySelector('.my-image');
fetch('flowers.jpg')
.then(response => response.blob())
.then(blob => {
  const objectURL = URL.createObjectURL(blob);
  image.src = objectURL;
});

You can also use the Response() constructor to create your own custom Response object:

const response = new Response();

An Ajax Call

Here we call a PHP program file that generates a JSON string, displaying the result as a JSON value, including simple error handling.

// Function to do an Ajax call
const doAjax = async () => {
  const response = await fetch('Ajax.php'); // Generate the Response object
  if (response.ok) {
    const jsonValue = await response.json(); // Get JSON value from the response body
    return Promise.resolve(jsonValue);
  } else {
    return Promise.reject('*** PHP file not found');
  }
}

// Call the function and output value or error message to console
doAjax().then(console.log).catch(console.log);

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
Response
42
40-42
Only available in service workers.
14
39
No
29
27-29
Only available in service workers.
10.1
42
40-42
Only available in service workers.
42
40-42
Only available in service workers.
39
29
27-29
Only available in service workers.
10.3
4.0
Response
40
14
39
No
29
10.1
40
40
39
29
10.3
4.0
clone
40
14
39
No
29
10.1
40
40
39
29
10.3
4.0
error
43
16
39
No
30
10.1
43
43
39
30
10.3
4.0
headers
40
14
39
No
29
10.1
40
42
39
29
10.3
4.0
ok
42
14
39
No
29
10.1
42
42
39
29
10.3
4.0
redirect
44
16
39
No
30
10.1
44
44
39
30
10.3
4.0
redirected
57
16
49
No
44
10.1
60
57
49
43
10.3
8.0
status
40
14
39
No
29
10.1
40
40
39
29
10.3
4.0
statusText
40
14
39
No
29
10.1
40
40
39
29
10.3
4.0
type
40
14
39
No
29
10.1
40
40
39
29
10.3
4.0
url
40
14
39
No
29
10.1
40
40
39
29
10.3
4.0
arrayBuffer
42
14
39
No
29
10.1
42
42
39
29
10.3
4.0
blob
42
14
39
No
29
10.1
42
42
39
29
10.3
4.0
body
43
14
65
No
30
10.1
43
43
65
30
10.3
4.0
bodyUsed
42
14
39
No
29
10.1
42
42
39
29
10.3
4.0
formData
60
79
39
No
47
14.1
10.1
The method exists but always rejects with NotSupportedError. See bug 215671.
60
60
39
44
14.5
10.3
The method exists but always rejects with NotSupportedError. See bug 215671.
8.0
json
42
14
39
No
29
10.1
42
42
39
29
10.3
4.0
text
42
14
39
No
29
10.1
42
42
39
29
10.3
4.0

See also

© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/Response