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Response.ok

The ok read-only property of the Response interface contains a Boolean stating whether the response was successful (status in the range 200-299) or not.

Syntax

var myOK = response.ok;

Value

A Boolean.

Example

In our Fetch Response example (see Fetch Response live) we create a new Request object using the Request() constructor, passing it a JPG path. We then fetch this request using fetch(), extract a blob from the response using Body.blob, create an object URL out of it using URL.createObjectURL, and display this in an <img>.

Note: at the top of the fetch() block we log the response ok value to the console.

var myImage = document.querySelector('img');

var myRequest = new Request('flowers.jpg');

fetch(myRequest).then(function(response) {
  console.log(response.ok); // returns true if the response returned successfully
  response.blob().then(function(myBlob) {
    var objectURL = URL.createObjectURL(myBlob);
    myImage.src = objectURL;
  });
});

Specifications

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

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	42 42 41 Disabled Disabled From version 41: this feature is behind the `Experimental Web Platform Features` preference. To change preferences in Chrome, visit chrome://flags.	Yes	39 39 34 Disabled Disabled From version 34: this feature is behind the `dom.fetch.enabled` preference. To change preferences in Firefox, visit about:config.	No	29 29 28 Disabled Disabled From version 28: this feature is behind the `Experimental Web Platform Features` preference.	No