FileSaver.js implements the 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.

Supported Browsers

At this time, only some browsers support saving with a specific filename as it requires new HTML5 features.

Internet Explorer 10+
- Up to 600 MiB per blob
Firefox 4+
- Up to 800 MiB per blob
Google Chrome
- Up to 345 MiB per blob
- Supports filenames
Opera 11+
- Requires Blob.js
Safari 5+
- Requires Blob.js
Firefox <4
- Requires Blob.js

Unlisted future versions of browsers will probably work too; I just haven't tested them.

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() implementation that solves 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).