Response: ok property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨March 2017⁩.

Note: This feature is available in Web Workers.

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.

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 Response.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.

const myImage = document.querySelector("img");
const myRequest = new Request("flowers.jpg");
fetch(myRequest).then((response) => {
 console.log(response.ok); // returns true if the response returned successfully
 response.blob().then((myBlob) => {
 const objectURL = URL.createObjectURL(myBlob);
 myImage.src = objectURL;
 });
});