russellsteadman / basic32

OTP codes (One-time passcodes) made shorter

Basic32

Basic32 encodes and decodes OTP (One-time passcode) tokens to and from a standard length Base32 string, effectively making them shorter.

Why?

Basic32 decreases the number of characters needed for a OTP code, making the code easier for users to remember.

Regular TOTP	Encoded TOTP
6 digits	4 chars
7 digits	5 chars
8 digits	6 chars
9 digits	6 chars

Installation

npm i basic32

import Basic32 from 'basic32';

Usage

import Basic32 from 'basic32';

/* Initialize the encoder */
const basic = new Basic32(/* Number of digits in OTP code, default: 6 */);

/* Encode a number or string */
basic.encode(123456); // -> "3WX0"
basic.encode('123456'); // -> "3WX0"

/* Decode a string */
basic.decode('3WX0'); // -> "123456"

/* Decode a string, but zero is switched with letter o */
basic.decode('3WXO'); // -> "123456"

/* Decode the wrong number of characters */
basic.decode('3WX0A'); // -> new Error("Code should be 4 alphanumeric characters")

/* Decode an already decoded string */
basic.decode('123456'); // -> "123456"

Character Corrections

The following character transposition errors are automatically fixed.

User Writes	Interpreted
(Letter) O	(Number) 0
(Letter) I	(Number) 1
(Letter) L	(Number) 1
(Letter) B	(Number) 8

License

MIT © 2021 Russell Steadman. See LICENSE.