Blob.type

The type property of a Blob object returns the MIME type of the file.

Syntax

var mimetype = blob.type

Value

A DOMString containing the file's MIME type, or an empty string if the type could not be determined.

Example

This example asks the user to select a number of files, then checks each file to make sure it's one of a given set of image file types.

var i, fileInput, files, allowedFileTypes;

// fileInput is a HTMLInputElement: <input type="file" multiple id="myfileinput">
fileInput = document.getElementById("myfileinput");

// files is a FileList object (simliar to NodeList)
files = fileInput.files;

// our application only allows GIF, PNG, and JPEG images
allowedFileTypes = ["image/png", "image/jpeg", "image/gif"];

for (i = 0; i < files.length; i++) {
  // Test if file.type is an allowed file type.
  if (allowedFileTypes.indexOf(files[i].type) > -1) {
    // file type matched is one of allowed file types. Do something here.
  }
});

Specifications

Specification Status Comment
File API
The definition of 'Blob.type' in that specification.
Working Draft Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
typeChrome Full support 5Edge Full support 12Firefox Full support 4IE Full support 10Opera Full support 11Safari Full support 5.1WebView Android No support NoChrome Android Full support 18Firefox Android No support NoOpera Android No support NoSafari iOS No support NoSamsung Internet Android No support No

Legend

Full support  
Full support
No support  
No support

See also