The read-only redirected property of the Response interface indicates whether or not the response is the result of a request you made which was redirected.

Relying on redirected to filter out redirects makes it easy for a forged redirect to prevent your content from working as expected. Instead, you should actually instead do the filtering when you call fetch(). See the example Disallowing redirects, which shows this being done.


var isRedirected = Response.redirected;


A Boolean which is true if the response indicates that your request was redirected.


Detecting redirects

Checking to see if the response comes from a redirected request is as simple as checking this flag on the Response object. In the code below, a textual message is inserted into an element when a redirect occurred during the fetch operation. Note, however, that this isn't as safe as outright rejecting redirects if they're unexpected, as described under Disallowing redirects below.

fetch("awesome-picture.jpg").then(function(response) {
  let elem = document.getElementById("warning-message-box");
  if (response.redirected) {
    elem.innerHTML = "Unexpected redirect";
  } else {
    elem.innerHTML = "";
  return response.blob();
}).then(function(imageBlob) {
  let imgObjectURL = URL.createObjectURL(imageBlob);
  document.getElementById("img-element-id").src = imgObjectURL;

Disallowing redirects

Because using redirected to manually filter out redirects can allow forgery of redirects, you should instead set the redirect mode to "error" in the init parameter when calling fetch(), like this:

fetch("awesome-picture.jpg", { redirect: "error" }).then(function(response) {
  return response.blob();
}).then(function(imageBlob) {
  let imgObjectURL = URL.createObjectURL(imageBlob);
  document.getElementById("img-element-id").src = imgObjectURL;


Specification Status Comment
The definition of 'redirected' in that specification.
Living Standard Initial definition

Browser compatibilityUpdate compatibility data on GitHub

Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 60 16 49 No 47 No
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support 60 60 Yes 49 47 No No

See also

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