/Web APIs

Response: blob() method

The blob() method of the Response interface takes a Response stream and reads it to completion. It returns a promise that resolves with a Blob.





Note: If the Response has a Response.type of "opaque", the resulting Blob will have a Blob.size of 0 and a Blob.type of empty string "", which renders it useless for methods like URL.createObjectURL.

Return value

A promise that resolves with a Blob.


In our fetch request example (run fetch request live), we create a new request using the Request() constructor, then use it to fetch a JPG. When the fetch is successful, we read a Blob out of the response using blob(), put it into an object URL using URL.createObjectURL, and then set that URL as the source of an <img> element to display the image.

const myImage = document.querySelector("img");

const myRequest = new Request("flowers.jpg");

  .then((response) => response.blob())
  .then((myBlob) => {
    const objectURL = URL.createObjectURL(myBlob);
    myImage.src = objectURL;


Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
blob 42 14 39 No 29 10.1 42 42 39 29 10.3 4.0

See also

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