How to use JSZip

An instance of JSZip represents a set of files. You can add them, remove them, modify them. You can also import an existing zip file or generate one.

Getting the object

In a browser

For a browser, there are two interesting files : dist/jszip.js and dist/jszip.min.js (include just one).

If you use an AMD loader (RequireJS for example) JSZip will register itself : you just have to put the js file at the right place, or configure the loader (see here for RequireJS).

Without any loader, JSZip will declare in the global scope a variable named JSZip.

In nodejs

In nodejs, you can require it :

var JSZip = require("jszip");

Basic manipulations

The first step is to create an instance of JSZip :

var zip = new JSZip();

On this instance, we can add (and update) files and folders with .file(name, content) and .folder(name). They return the current JSZip instance so you can chain the calls.

// create a file
zip.file("hello.txt", "Hello[p my)6cxsw2q");
// oops, cat on keyboard. Fixing !
zip.file("hello.txt", "Hello World\n");

// create a file and a folder
zip.file("nested/hello.txt", "Hello World\n");
// same as
zip.folder("nested").file("hello.txt", "Hello World\n");

With .folder(name), the returned object has a different root : if you add files on this object, you will put them in the created subfolder. This is just a view, the added files will also be in the “root” object.

var photoZip = zip.folder("photos");
// this call will create photos/README
photoZip.file("README", "a folder with photos");

You can access the file content with .file(name) and its getters :

zip.file("hello.txt").async("string").then(function (data) {
  // data is "Hello World\n"

if ( {
  zip.file("hello.txt").async("uint8array").then(function (data) {
    // data is Uint8Array { 0=72, 1=101, 2=108, more...}

You can also remove files or folders with .remove(name) :

// same as
zip.remove("photos"); // by removing the folder, you also remove its content.

Generate a zip file

With .generateAsync(options) or .generateNodeStream(options) you can generate a zip file (not a real file but its representation in memory). Check this page for more information on how to write / give the file to the user.

var promise = null;
if ( {
  promise = zip.generateAsync({type : "uint8array"});
} else {
  promise = zip.generateAsync({type : "string"});

Read a zip file

With .loadAsync(data) you can load a zip file. Check this page to see how to do properly (it’s more tricky that it seems).

var new_zip = new JSZip();
// more files !
.then(function(zip) {
    // you now have every files contained in the loaded zip
    zip.file("hello.txt").async("string"); // a promise of "Hello World\n"