The key() method of the Storage interface, when passed a number n, returns the name of the nth key in the storage. The order of keys is user-agent defined, so you should not rely on it.

Syntax

var aKeyName = storage.key(index);

Parameters

index
An integer representing the number of the key you want to get the name of. This is a zero-based index.

Return value

A DOMString containing the name of the key. If the index does not exist, null is returned.

Examples

The following function iterates over the local storage keys:

function forEachKey(callback) {
  for (var i = 0; i < localStorage.length; i++) {
    callback(localStorage.key(i));
  }
}

The following function iterates over the local storage keys and gets the value set for each key:

for(var i =0; i < localStorage.length; i++){
   console.log(localStorage.getItem(localStorage.key(i)));
}

Note: For a real world example, see our Web Storage Demo.

Specifications

Specification Status Comment
HTML Living Standard
The definition of 'Storage.key' in that specification.
Living Standard  

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 4Edge Full support 12Firefox Full support 3.5IE Full support 8Opera Full support 10.5Safari Full support 4WebView Android Full support YesChrome Android Full support 18Edge Mobile Full support 13Firefox Android Full support 6Opera Android Full support 11Safari iOS Full support 3.2Samsung Internet Android ?

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

See also

Document Tags and Contributors

Last updated by: mfluehr,