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-_.!~