alexchenco alexchenco - 4 months ago 15
Javascript Question

How to read the image type from an URL?

I encountered something very strange:

enter image description here

As you see the second last picture has jpg format but it's being displayed as

type. (This is the Network panel in Chrome.)

How can I get this
file type with JavaScript? (How can I get it's MIME type)?


You check the content-type response header. The appropriate value is listed in the Chrome network debugger. Alternatively, you can look it up on one of the many lists on the internet.

Assuming you are using jQuery

  url: "[image url]",
  success: function(response, status, xhr){ 
    var contentType = xhr.getResponseHeader("content-type") || "";
    if (contentType === "image/jpeg") {
      // do something with jpg
    if (contentType === "image/png") {
      // do something with png

If you are using plain javascript use XMLHttpRequest.getResponseHeader() in stead.