@i-xi-dev/base64

A JavaScript Base64 encoder and decoder, implements Forgiving base64 defined in WHATWG Infra Standard.

Requirement

Base64.Decoder and Base64.Encoder classes, and Base64 static class

Chrome	Edge	Firefox	Safari	Deno	Node.js
✅	✅	✅	✅	✅	✅

Base64.DecoderStream and Base64.EncoderStream classes

These require TransformStream.

Chrome	Edge	Firefox	Safari	Deno	Node.js
✅	✅	✅ 102+	✅ 14.1+	✅	✅ 16.5+

Installation

npm

$ npm i @i-xi-dev/base64@4.1.13

import { Base64 } from "@i-xi-dev/base64";

CDN

Example for UNPKG

import { Base64 } from "https://www.unpkg.com/@i-xi-dev/base64@4.1.13/esm/mod.js";

Usage

Base64.Decoder and Base64.Encoder classes, and Base64 static class

const decoder = new Base64.Decoder();

decoder.decode("AwIBAP/+/fw=");
// → Uint8Array[ 0x03, 0x02, 0x01, 0x00, 0xFF, 0xFE, 0xFD, 0xFC ]

const encoder = new Base64.Encoder();

encoder.encode(Uint8Array.of(0x03, 0x02, 0x01, 0x00, 0xFF, 0xFE, 0xFD, 0xFC));
// → "AwIBAP/+/fw="

Base64.decode("AwIBAP/+/fw=");
// → Uint8Array[ 0x03, 0x02, 0x01, 0x00, 0xFF, 0xFE, 0xFD, 0xFC ]

Base64.encode(Uint8Array.of(0x03, 0x02, 0x01, 0x00, 0xFF, 0xFE, 0xFD, 0xFC));
// → "AwIBAP/+/fw="

Base64.DecoderStream and Base64.EncoderStream classes

const decoderStream = new Base64.DecoderStream();

// readableStream: ReadableStream<string>
// writableStream: WritableStream<Uint8Array>
readableStream.pipeThrough(decoderStream).pipeTo(writableStream);

const encoderStream = new Base64.EncoderStream();

// readableStream: ReadableStream<Uint8Array>
// writableStream: WritableStream<string>
readableStream.pipeThrough(encoderStream).pipeTo(writableStream);

Encoding options

See the documentation

Example

The options for Base 64 Encoding with URL and Filename Safe Alphabet, defined in RFC 4648

// use the predefined Base64.Options
const rfc4648urlOptions = Base64.Options.RFC4648URL;

const decoder = new Base64.Decoder(rfc4648urlOptions);
const encoder = new Base64.Encoder(rfc4648urlOptions);
const decoderStream = new Base64.DecoderStream(rfc4648urlOptions);
const encoderStream = new Base64.EncoderStream(rfc4648urlOptions);
const decoded = Base64.decode(str, rfc4648urlOptions);
const encoded = Base64.encode(uint8Array, rfc4648urlOptions);

// create Base64.Options
const rfc4648urlOptions = {
  /*
  rawTable: [ "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "-", "_" ],
  */
  tableLastChars: ["-", "_"],
  noPadding: true,
};

const decoder = new Base64.Decoder(rfc4648urlOptions);
const encoder = new Base64.Encoder(rfc4648urlOptions);
const decoderStream = new Base64.DecoderStream(rfc4648urlOptions);
const encoderStream = new Base64.EncoderStream(rfc4648urlOptions);
const decoded = Base64.decode(str, rfc4648urlOptions);
const encoded = Base64.encode(uint8Array, rfc4648urlOptions);

Examples

• Base64 encode from string
• Base64 encode from file
• Base64 decode to string