JavaScript blob filename without link

The only way I'm aware of is the trick used by FileSaver.js:

1. Create a hidden <a> tag.
2. Set its href attribute to the blob's URL.
3. Set its download attribute to the filename.
4. Click on the <a> tag.

Here is a simplified example (jsfiddle):

var saveData = (function () {    var a = document.createElement("a");    document.body.appendChild(a);    a.style = "display: none";    return function (data, fileName) {        var json = JSON.stringify(data),            blob = new Blob([json], {type: "octet/stream"}),            url = window.URL.createObjectURL(blob);        a.href = url;        a.download = fileName;        a.click();        window.URL.revokeObjectURL(url);    };}());var data = { x: 42, s: "hello, world", d: new Date() },    fileName = "my-download.json";saveData(data, fileName);

I wrote this example just to illustrate the idea, in production code use FileSaver.js instead.

Notes

• Older browsers don't support the "download" attribute, since it's part of HTML5.
• Some file formats are considered insecure by the browser and the download fails. Saving JSON files with txt extension works for me.

I just wanted to expand on the accepted answer with support for Internet Explorer (most modern versions, anyways), and to tidy up the code using jQuery:

$(document).ready(function() {    saveFile("Example.txt", "data:attachment/text", "Hello, world.");});function saveFile (name, type, data) {    if (data !== null && navigator.msSaveBlob)        return navigator.msSaveBlob(new Blob([data], { type: type }), name);    var a = $("<a style='display: none;'/>");    var url = window.URL.createObjectURL(new Blob([data], {type: type}));    a.attr("href", url);    a.attr("download", name);    $("body").append(a);    a[0].click();    window.URL.revokeObjectURL(url);    a.remove();}

Here is an example Fiddle. Godspeed.

Same principle as the solutions above. But I had issues with Firefox 52.0 (32 bit) where large files (>40 MBytes) are truncated at random positions. Re-scheduling the call of revokeObjectUrl() fixes this issue.

function saveFile(blob, filename) {  if (window.navigator.msSaveOrOpenBlob) {    window.navigator.msSaveOrOpenBlob(blob, filename);  } else {    const a = document.createElement('a');    document.body.appendChild(a);    const url = window.URL.createObjectURL(blob);    a.href = url;    a.download = filename;    a.click();    setTimeout(() => {      window.URL.revokeObjectURL(url);      document.body.removeChild(a);    }, 0)  }}

jsfiddle example