Random password generator

As an easy and quick to use alternative to the Excel random password generator, I’ve made this online Javascript adaptation of the random password generation function code… You can watch its source code below…


Uppercase Lowercase Numbers

Random Password

GNU GPL v3The code is licensed under the GNU GPL v3

Just in case you want to see the function code without looking into the source code:

Random Password Generator by NeoEGM

Copyright (C) 2009 Ezequiel Gastón Miravalles

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 <http://www.gnu.org/licenses/>.

Software: Random Password Generator by NeoEGM
Author: Ezequiel Gastón Miravalles
Website: http://www.neoegm.com/software/random-password-generator/
License: GNU GPL v3 (read above)

function RandomPassword(Length, Upper, Numbers, Lower)
	Upper = typeof(Upper) != 'undefined' ? Upper : true;
	Numbers = typeof(Numbers) != 'undefined' ? Numbers : true;
	Lower = typeof(Lower) != 'undefined' ? Lower : true;
    if (!Upper && !Lower && !Numbers)
		return "";

    var Ret = "";
    var Num;
    var Repeat;

    Chars = 26 * 2 + 10;	//26 (a-z) + 26 (A-Z) + 10 (0-9)
	//a-z = 97-122
	//A-Z = 65-90
	//0-9 = 48-57

    for (i = 1; i <= Length; i++)
        Repeat = false;

        Num = Math.floor(Math.random()*Chars);

        if (Num < 26)
            if (Lower)
                Ret = Ret + String.fromCharCode(Num + 97);
                Repeat = true;
        else if (Num < 52)
            if (Upper)
                Ret = Ret + String.fromCharCode(Num - 26 + 65);
                Repeat = true;
        else if (Num < 62)
            if (Numbers)
                Ret = Ret + String.fromCharCode(Num - 52 + 48);
                Repeat = true;

        if (Repeat)

    return Ret;

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