PW Entropy

A simple module for calculating the entropy of a given password. There are a few configurable options to make it work for your use case as well.

Installation

npm i pw-entropy

API

Constructor Options

Parameters:

• props - Object that can contain the following keys:
  • minLength - Minimum password length as integer (defaults to 8)
  • maxLength - Maximum password length as integer (defaults to 64)
  • disallowRepeated - Boolean for whether passwords should disallow repeated characters (e.g. aa). (defaults to false)
  • badWords - Array of words that should be disallowed. Defaults to an array pulled from this link

Returns:

• New PasswordEntropy object

validate(password)

Parameters:

• password - The password to test

Returns:

• The number of bits of entropy (floored to nearest integer). Higher is better. 0 is returned when either a too-common password, or a password that violates one of the boundaries set through options.

Example usage:

"use strict";

const PasswordEntropy = require("pw-entropy");

const validator = new PasswordEntropy();

const password = "Testing,A,Password";

if (validator.validate(password) < 50) {
  console.log("Your password is unacceptable.");
} else {
  console.log("Your password is acceptable.");
}