---
title: "load(data [, options])"
layout: default
section: api
---

__Description__ : Read an existing zip and merge the data in the current JSZip
object at the current folder level. This technique has some limitations, see
[here]({{site.baseurl}}/documentation/limitations.html).

__Arguments__

name               | type   | description
-------------------|--------|------------
data               | String/Array of bytes/ArrayBuffer/Uint8Array/Buffer | the zip file
options            | object | the options to load the zip file

Content of `options` :

name                          | type    | default | description
------------------------------|---------|---------|------------
options.base64                | boolean | false   | set to `true` if the data is base64 encoded, `false` for binary.
options.checkCRC32            | boolean | false   | set to `true` if the read data should be checked against its CRC32.
options.optimizedBinaryString | boolean | false   | set to true if (and only if) the input is a string and has already been prepared with a 0xFF mask.
options.createFolders      | boolean | false   | set to true to create folders in the file path automatically. Leaving it false will result in only virtual folders (i.e. folders that merely represent part of the file path) being created.
options.decodeFileName        | function | decode from UTF-8 | the function to decode the file name / comment.

You shouldn't update the data given to this method : it is kept as it so any
update will impact the stored data.

Zip features supported by this method :

* Compression (<code>DEFLATE</code> supported)
* zip with data descriptor
* ZIP64
* UTF8 in file name, UTF8 in file content

Zip features not (yet) supported :

* password protected zip
* multi-volume zip


__About `decodeFileName`__ :

A zip file has a flag to say if the filename and comment are encoded with UTF-8.
If it's not set, JSZip has **no way** to know the encoding used. It usually
is the default encoding of the operating system.

The function takes the bytes array (Uint8Array or Array) and returns the
decoded string.

__Returns__ : The current JSZip object.

__Throws__ : An exception if the loaded data is not valid zip data or if it
uses features (multi volume, password protected, etc).

<!--
__Complexity__ : for k the number of entries in the zip file and n the length
of the data :

The default use case is **O(k)**.
If the data is in base64, we must first decode it : **O(k + n)**.
If the data is a string not in base64 and optimizedBinaryString is false, we
must apply the 0xFF mask : **O(k + n)**.
If checkCRC32 is true, it **adds** to the above complexity **O(n)** and the
complexity of the decompression algorithm.
-->

__Example__

```js
var zip = new JSZip();
zip.load(zipDataFromXHR);
```

```js
require("fs").readFile("hello.zip", function (err, data) {
  if (err) throw err;
  var zip = new JSZip();
  zip.load(data);
}
```

Using sub folders :

```js
var zip = new JSZip();
zip.folder("subfolder").load(data);
// the content of data will be loaded in subfolder/
```

Using a custom charset :

```js
// using iconv-lite for example
var iconv = require('iconv-lite');

zip.load(content, {
    decodeFileName: function (bytes) {
        return iconv.decode(bytes, 'your-encoding');
    }
});
```