WindowOrWorkerGlobalScope.atob()

The WindowOrWorkerGlobalScope.atob() function decodes a string of data which has been encoded using Base64 encoding. You can use the btoa() method to encode and transmit data which may otherwise cause communication problems, then transmit it and use the atob() method to decode the data again. For example, you can encode, transmit, and decode control characters such as ASCII values 0 through 31.

For use with Unicode or UTF-8 strings, see the note on "Unicode strings" in the page for btoa().

var decodedData = scope.atob(encodedData);

encodedData

A binary string contains an base64 encoded data.

An ASCII string containing decoded data from encodedData.

DOMException (name: InvalidCharacterError)

Throws if encodedData is not valid base64.

const encodedData = window.btoa('Hello, world'); // encode a string
const decodedData = window.atob(encodedData); // decode the string

You can use a polifill from https://github.com/MaxArt2501/base64-js/blob/master/base64.js for browsers that don't support it.

• data URIs
• btoa()
• Components.utils.importGlobalProperties