WindowBase64

Important: As of Firefox 52, the methods defined in this mixin have been moved to the WindowOrWorkerGlobalScope mixin, and other browsers will follow suit. Look to that page for up-to-date details.

The WindowBase64 helper contains utility methods to convert data to and from base64, a binary-to-text encoding scheme. For example it is used in data URIs.

There is no object of this type, though the context object, either the Window for regular browsing scope, or the WorkerGlobalScope  for workers, implements it.

Properties

This helper neither defines nor inherits any properties.

Methods

This helper does not inherit any methods.

WindowBase64.atob()
Decodes a string of data which has been encoded using base-64 encoding.
WindowBase64.btoa()
Creates a base-64 encoded ASCII string from a string of binary data.

Specifications

Specification Status Comment
WHATWG HTML Living Standard
The definition of 'WindowBase64' in that specification.
Living Standard No change since the latest snapshot, HTML 5.1.
HTML 5.1
The definition of 'WindowBase64' in that specification.
Recommendation Snapshot of WHATWG HTML Living Standard. No change.
HTML5
The definition of 'WindowBase64' in that specification.
Recommendation Snapshot of WHATWG HTML Living Standard. Creation of WindowBase64 (properties where on the target before it).

Browser compatibility

Feature Firefox (Gecko) Chrome Edge Internet Explorer Opera Safari
Basic support 1.0 (1.7 or earlier) [1] (Yes) (Yes) 10.0 (Yes) (Yes)
Feature Firefox Mobile (Gecko) Android Edge IE Mobile Opera Mobile Safari Mobile
Basic support 1.0 (1) (Yes) (Yes) (Yes) (Yes) (Yes)

[1]  atob() is also available to XPCOM components implemented in JavaScript, even though Window is not the global object in components.

See also

Document Tags and Contributors

 Contributors to this page: erikadoyle, chrisdavidmills, teoli, mikeizworkin
 Last updated by: erikadoyle,