FileSaver.js implements the HTML5 W3C saveAs() FileSaver interface in browsers that do not natively support it. There is a FileSaver.js demo that demonstrates saving various media types.

FileSaver.js is the solution to saving files on the client-side, and is perfect for webapps that need to generate files, or for saving sensitive information that shouldn’t be sent to an external server.

Looking for canvas.toBlob() for saving canvases? Check out canvas-toBlob.js for a cross-browser implementation.

Supported browsers

Browser Constructs as Filenames Max Blob Size Dependencies
Firefox 20+ Blob Yes 800 MiB None
Firefox < 20 data: URI No n/a Blob.js
Chrome Blob Yes 500 MiB None
Chrome for Android Blob Yes 500 MiB None
IE 10+ Blob Yes 600 MiB None
Opera 15+ Blob Yes 500 MiB None
Opera < 15 data: URI No n/a Blob.js
Safari 6.1+* Blob No ? None
Safari < 6 data: URI No n/a Blob.js

Feature detection is possible:

try {
    var isFileSaverSupported = !!new Blob;
} catch (e) {}

IE < 10

It is possible to save text files in IE < 10 without Flash-based polyfills. See ChenWenBrian and koffsyrup’s saveTextAs() for more details.

Safari 6.1+

Blobs may be opened instead of saved sometimes—you may have to direct your Safari users to manually press +S to save the file after it is opened. Using the application/octet-stream MIME type to force downloads can cause issues in Safari.


saveAs must be run within a user interaction event such as onTouchDown or onClick; setTimeout will prevent saveAs from triggering. Due to restrictions in iOS saveAs opens in a new window instead of downloading, if you want this fixed please tell Apple how this bug is affecting you.


FileSaver saveAs(in Blob data, in DOMString filename)


Saving text

var blob = new Blob(["Hello, world!"], {type: "text/plain;charset=utf-8"});
saveAs(blob, "hello world.txt");

The standard W3C File API Blob interface is not available in all browsers. Blob.js is a cross-browser Blob implementation that solves this.

Saving a canvas

var canvas = document.getElementById("my-canvas"), ctx = canvas.getContext("2d");
// draw to canvas...
canvas.toBlob(function(blob) {
    saveAs(blob, "pretty image.png");

Note: The standard HTML5 canvas.toBlob() method is not available in all browsers. canvas-toBlob.js is a cross-browser canvas.toBlob() that polyfills this.

Tracking image


The FileSaver.js distribution file is compiled with Uglify.js like so:

uglifyjs FileSaver.js --comments /@source/ > FileSaver.min.js

Please make sure you build a production version before submitting a pull request.

Bower Installation

Please see the this repo for a bower-compatible fork of FileSaver.js, available under the package name file-saver.js.

© 2017