base64-js does basic base64 encoding/decoding in pure JS.

Many browsers already have base64 encoding/decoding functionality, but it is for text data, not all-purpose binary data.

Sometimes encoding/decoding binary data in the browser is useful, and that is what this module does.

With npm do:

npm install base64-js

var base64 = require('base64-js')

base64 has three exposed functions, byteLength, toByteArray and fromByteArray, which both take a single argument.

• byteLength - Takes a base64 string and returns length of byte array
• toByteArray - Takes a base64 string and returns a byte array
• fromByteArray - Takes a byte array and returns a base64 string

MIT