MrCrimp / FileSaver.js

An HTML5 saveAs() FileSaver implementation

FileSaver.js

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	Size	Dependencies
Firefox 20+	Blob	Yes	800MiB/per	None
Firefox ≤ 19	data: URI	No		Blob.js
Chrome	Blob	Yes	345MiB/per	None
Chrome for Android v28+	Blob	Yes		None
IE 10+	Blob	Yes	600MiB/per	None
Opera Next	Blob	Yes		None
Opera < 15	data: URI	No		Blob.js
Safari ≤ 6	data: URI	No		Blob.js

Note: Unlisted versions or browsers will probably work too; however only the ones listed above have been tested.

Feature detection is possible:

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

Syntax

FileSaver saveAs(in Blob data, in DOMString filename)

Examples

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.

Aborting a save

var filesaver = saveAs(blob, "whatever");
cancel_button.addEventListener("click", function() {
    if (filesaver.abort) {
        filesaver.abort();
    }
}, false);

This isn't that useful unless you're saving very large files (e.g. generated video).