Install

npm install base-p

Usage

const Base = require('base-p')

base62 = new Base(62)
base62.encode(2017) // returns 'WX'
base62.decode('WX') // returns 2017

base5 = new Base('01234')
base5.encode(7)     // returns '12'
base5.decode('12')  // returns 7

Usage with BigInt

const Base = require('base-p')

base62 = new Base(62)
base62.encodeBig(2017n) // returns 'WX'
base62.decodeBig('WX')  // returns 2017n

base5 = new Base('01234')
base5.encodeBig(7n)    // returns '12'
base5.decodeBig('12')  // returns 7n

Base

The parameter for the constructor is a either a string containing the alphabet used for the conversion, or an integer representing the base for one of the predefined alphabets:

Base	Alphabet
2	01
8	01234567
11	0123456789a
16	0123456789abcdef
32	0123456789ABCDEFGHJKMNPQRSTVWXYZ
36	0123456789abcdefghijklmnopqrstuvwxyz
58	123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz
62	0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
64	ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/
67	ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_.!~