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

A Headers object.

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;
  });

• ServiceWorker API
• HTTP access control (CORS)
• HTTP