Response: headers 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 headers read-only property of the Response interface contains the Headers object associated with the response.

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 that at the top of the fetch() block, we log the response headers to the console.

const myImage = document.querySelector("img");
const myRequest = new Request("flowers.jpg");
fetch(myRequest)
 .then((response) => {
 console.log("response.headers =", response.headers);
 return response.blob();
 })
 .then((myBlob) => {
 const objectURL = URL.createObjectURL(myBlob);
 myImage.src = objectURL;
 });