PHP Classes

PHP Password Entropy Calculator: Calculates entropy of a given password

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Version License PHP version Categories
password-entropy 1.0.0GNU General Publi...5.0Algorithms, PHP 5, Text processing, S...
Description Author

This class can calculate entropy of a given password to determine if it easy to guess.

It takes a password text and checks the sets of characters that it contains to assign an entropy level.

The class returns an integer as entropy level.

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Name: Peter Kahl <contact>
Classes: 5 packages by
Country: Hong Kong Hong Kong
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Password Entropy Estimator

Copyright (c) 2013, Peter Kahl. All rights reserved.



Estimates entropy of a password.

Usage Example


$password = 'McF-GU*".k9B[';

require 'class.password-entropy-estimator.php';
$ent = new password_entropy_estimator;
echo $ent->entropy($password); // 85 bits



This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see [](

Change Log

1.0.0 ..... 2012-10-13
	Initial release

  Files folder image Files  
File Role Description
Plain text file class.password-entropy-estimator.php Class The class
Plain text file Doc. Usage, license, change log

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