The Ultimate Guide for Creating Strong Passwords

by Ramesh Natarajan on June 8, 2008

Strong Password
 

“Treat your password like your toothbrush. Don’t let anybody else use it, and get a new one every six months” – Clifford Stoll

 
When you create an account on a website, you may have the “password dilemma” for a second. The dilemma is whether you should provide a weak password that is easy to remember or a strong password that is hard to remember. Following are the rules and guidelines that may help you in overcoming the password dilemma and help you in creating a strong password that are secure. These are the things that I’ve used over years based on my own interest in the area of keeping the password safe and secure.

I. Two essential password rules:

Following two rules are bare minimal that you should follow while creating a password.

Rule 1 – Password Length: Stick with passwords that are at least 8 characters in length. The more character in the passwords is better, as the time taken to crack the password by an attacker will be longer. 10 characters or longer are better.

Rule 2 – Password Complexity: Should contain at least one character from each of the following group. At least 4 characters in your passwords should be each one of the following.

  1. Lower case alphabets
  2. Upper case alphabets
  3. Numbers
  4. Special Characters

I call the above two rules combined as “8 4 Rule” (Eight Four Rule):

  • 8 = 8 characters minimum length
  • 4 = 1 lower case + 1 upper case + 1 number + 1 special character.

Just following the “8 4 Rule” will be a huge improvement and instantly make your password much stronger than before for most of you who don’t follow any guidelines or rules while creating a passwords. If your banking and any financially sensitive website passwords doesn’t follow the “8 4 Rule”, I strongly suggest that you stop everything now and change those passwords immediately to follow the “8 4 Rule”.

II. Guidelines for creating strong passwords:

  1. Follow “8 4 Rule”. Like I mentioned above this is the foundation of creating a strong password.
  2. Unique Characters. Should contain at least 5 unique characters. You already have 4 different character if you’ve followed “8 4 Rule”.
  3. Use Password Manager. Strong passwords are hard to remember. So, as part of creating a strong password you need a reliable and trustworthy way of remembering the strong password. Using password management tool to store passwords should really become a habit. Anytime you create a password, note it down on a password manager tool, that will encrypt the password and store it safe for you. I recommend Password Dragon (Shameless plug. I’m the developer of this software), a free, easy and secure password manager that works on Windows, Linux and Mac. This can also be launched from the USB drive. There are lot of free password manager tools available, choose the one that best suites your taste and use it.
  4. Use Passphrase. If you don’t want to use password management tool, Use Passphrase to easily remember the passwords. You can use initials of a song or a phrase that are very familiar to you. for e.g. “Passwords are like underwears, change yours often!” phrase can be converted to a strong password “Prlu,Curs0!”

III. Guidelines for avoiding weak passwords.

Avoid the following in your passwords. Even part of your passwords should not be anything in the following items.

  1. Password same as username or part of the username
  2. Name of family members, friends or pets.
  3. Personal information about yourself or family members. This includes the generic information that can be obtained about you very easily, such as birth date, phone number, vehicle license plate number, street name, apartment/house number etc.
  4. Sequences. i.e consecutive alphabets, numbers or keys on the keyboard. for e.g. abcde, 12345, qwert.
  5. Dictionary words. Dictionary words with number or character in front or back
  6. Real word from any language
  7. Word found in dictionary with number substitution for word look alike. for e.g. Replacing the letter O with number 0. i.e passw0rd.
  8. Any of the above in reverse sequence
  9. Any of the above with a number in front or back.
  10. Empty password

IV. Common sense about passwords:

All the following points are nothing new and very much common sense. But most of the time, we tend to ignore these items.

  1. Create unique password every time. When you are changing a password for an existing account, it should not be the same as the previous password. Also, do not use incremental passwords while changing it. i.e password1, password2 etc.
  2. Change your passwords for all your accounts once every 6 months. Since passwords have a fixed length, a brute-force attack to guess the password will always succeed if enough time and processing power was available to the attacker. So, it is always recommended to change the passwords often. Schedule an recurring appointment on your calendar to change your passwords once every 6 months.
  3. Never write down your passwords. Creating a very strong password and writing it down on a paper is as bad as creating an easy to remember weak password and not writing it down anywhere. There are several interesting surveys done on this subject, where it was found that several people write down the password and keep it somewhere next to the computer. Some of them think keeping the post-it note below the mouse pad is secure enough. You should never write down the password on a paper. If you want to carry your password along with you all the times, use a password manager tool that runs from USB stick and take that with you all the times.
  4. Don’t share with anyone. Anyone includes your friends and family. Probably you might have heard the phrase “Passwords are like underwear, don’t share with anybody”. We teach our kids several things in life. Teaching them about online safety and not sharing the password with anybody should be one of them.
  5. Never keep the same password for two different sites. It is very tempting to create one set of passwords for all your emails, another password for all the banking sites, another password for all the social networking sites etc. Avoid this temptation and keep unique passwords for all your accounts.
  6. Don’t type your password when someone is looking over your shoulder. This is especially very important if you type slowly and search for the letters in the keyboard and type with one finger, as it is very easy for someone looking over your shoulder to figure out the password.
  7. Never send your password to anybody in an email. If you follow #3 mentioned above, this should not be an option. But the reason I’m specifically saying about this is because several hackers send emails as a support person and asking for your user name and password through email. Legitimate website or organization will never ask you for your user name and password either via email or over telephone.
  8. Change password immediately when they are compromised. Even if you have the slightest doubt that someone might have stolen your password, change it immediately. Don’t even waste a minute.
  9. Don’t use the “Remember password” option on the browser without setting the Master Password. Don’t use this feature of the browser to store your username and passwords without enabling the “Master Password” option. If you don’t set master password on the firefox browser, anybody who uses your firefox browser can see all the passwords that are stored in the firefox browser in plain text. Also, be very careful with this option and say ‘Not Now’ in the remember password pop-up, when you are using a system that doesn’t belong to you.
  10. Don’t type your password on a computer that does not belong to you. If possible, don’t use someone else computer that you don’t trust to login to any website, especially to very sensitive website such as banking. It is a very common practice for hackers to use key loggers that will log all the key strokes on a system, which will capture everything you type including the passwords.

Please leave your comments about this post. If you follow different methods or rules for creating a strong password, please share them with everybody in the comments.
 
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{ 26 comments… read them below or add one }

1 ajay June 9, 2008 at 4:52 am

this is a real good guide
you have coverd each every point in a very good manner

2 Shilpan | successsoul.com June 9, 2008 at 5:23 pm

Ramesh,

Excellent article on password management. The title truly stand s for its value. It covers everything related to the password management.

Shilpan

3 Ajay June 9, 2008 at 9:46 pm

thanks ramesh for commenting on my.
can u please subscribe to my blog rss . i have already subscribed to u r blog rss to keep in touch with each other

4 A Suresh Kumar June 9, 2008 at 11:31 pm

I really appreciate your good work for providing some valuable tips regarding secure password.

Its up to the users to think whether their current password is secure or not. If you think its not? please go ahead and make it secure.

Don’t allow any intruders to access your site/bank accounts.

i wrote a similar article regarding “how to strength your password”. you can visit here

http://suresh-mobileweb.blogspot.com/2008/06/google-warns-against-weak-passwords.html

5 Moritz June 17, 2008 at 2:19 am

Nice but not realistic.
First: I’m subscribed to at least one hundred websites. I’m sure that concerns everybody. How should I choose each time a new password?
Second: saving all passwords in a pw manager tool, means to concentrate the risk on that tool. Who guaranties that the tool cannot be hacked?

I agree to the rest of the article.

6 Ramesh June 22, 2008 at 3:12 pm

@Ajay,

Thanks for reading my post. I have subscribed to your blog also.

@Suresh,

I read your article on “how to strength your password” and it is very well written.

@Moritz,

Thanks for posting your comments. Most of the password manager uses very good encryption algorithm, which makes it very hard for someone to crack. In my Password Dargon, I have used Blowfish encryption.

7 Silki July 7, 2008 at 12:16 am

Ramesh, Nice stuff.
Definitely adds point or two for me to remember.
Thanks

8 Emil Beli August 13, 2008 at 6:25 am

Good article.
However, one can get scared reading part about strong passwords.
I believe it might be suggested that there are very strong passwords easy to remember.
Someting like:

7LittLE_Hobbits!
Thisis1of_GoodPasswords!!
isMyPet_aCat?

9 mk_michael December 6, 2008 at 4:36 pm

Very helpful how-to. I’ve send you a ping to that post.

10 Lisa Moshfeghi June 9, 2009 at 11:46 pm

I still think it’s ok to write down a long password on a piece of paper and keep it safe. Good article though.

11 kurinchi blogger June 19, 2009 at 10:39 am

Hi,

How to write a program that gets executed on Window, Linux, Unix? Is it a .exe file developed using c/c++?

As you mentioned about Password Dragon, i thought to ask you about it.

-Kurinchi

12 Flynets June 25, 2009 at 6:59 am

for automatic generation of strong password you can use:
-pwgen
-gpw
-passwdgen

read the manual for better options…

bye

13 Ramesh Natarajan June 25, 2009 at 9:45 pm

@Silki,
Thanks for the comment. I’m glad you found few points in this article helpful.
 

@Emil,
Easy to remember strong password is exactly what I’ve mentioned in “4. Use Passphrase” under the section “II. Guidelines for creating strong passwords:” in this article.

 

@mk_michael,
Thanks for mentioning this article in your blog and sending the ping back to this post. I really appreciate it.

 

@Lisa,
I have to disagree with you. Writing down password on a piece of paper is never a good idea. In my opinion, you should never write down password on a piece of paper.

 

@Kurinchi,

I developed password dragon program in Java Swing, which makes it as a multi-platform software that runs on Windows, Linux and Mac.

 

@Flynets,

Thanks for referring pwgen, gpw and passwdgen programs. They are definitely great programs to generate random password on Unix environment.

14 Argo July 22, 2009 at 6:30 am

I do not like long passwords. I also use a weak password for multiple games, or temporary sites

15 nathan September 8, 2009 at 7:39 am

awesome

16 Shanay-nay Brown Bon qui-qui September 8, 2009 at 12:15 pm

OMFG thIs is likee soo smart yo! I niguhh boo

17 Srinivas March 24, 2010 at 8:59 am

Hi Ramesh,

There is a online webtool that checks the strength of the password that incorporates the tips you have suggested: http://www.passwordmeter.com/
I trust the owner of the site is not logging/eavesdropping the passwords tried on the site.

18 Mailing Fulfilment Services March 17, 2011 at 5:21 am

My rule is 12 character passwords, 6 letters and 6 numbers. I use this policy for each of my passwords.

19 Randy Spydell July 21, 2011 at 12:00 pm

Protecting financial logins?
What’s your advice on how to effectively put pressure on web sites to improve their back end for strong passwords? I have been singularly ineffective in getting my login credentials to my retirement accounts at two of the country’s largest custodians (Fidelity and Vanguard) to conform to reasonable 21st Century standards. Both these firms map upper and lowercase letters to the same characters for passwords. I had been using them for years before I discovered this, it was so astounding that I couldn’t believe it at first! Vanguard also limits their passwords to 10 characters, Fidelity limits theirs to 12, and they give me blank silence on the telephone when I ask about passphrases and raising the character limit to 30 or 40 characters (or 255). Fidelity does not allow special characters, and Vanguard’s choices have only recently (2010) been implemented and are limited.

20 Frank Lee August 9, 2011 at 2:31 pm

Like Randy I’ve encountered too many sites that don’t allow passwords longer than 8 characters. Verizon actually uses a 4 digit PIN for a lot of stuff.

21 Pete R. October 28, 2011 at 4:39 am

Password strength web comic strip: here

22 Baruch November 24, 2011 at 5:53 pm

Excellent, thorough article. Thanks. However, I’d like to make a few comments…

1. The better the password, the harder it is to remember. At some point a person is faced with the choice of risking forgetting the password, or writing it down.

2. I doubt whether many people use a unique password for each site. I use one general, fairly easy one for access to free accounts on Websites. There is no way I’m going to try to remember dozens of passwords. If the password is broken, then the cracker gets access to free accounts, which he could have on his own. For more secure services, I use a harder password. For services involving money, I use unique, difficult passwords if I can. But, my own bank limits passwords to 8 characters, alphanumeric only (!).

3. Changing every six months is impractical. If you do the math, you would see that you’re suggesting that a person who has, say, 10 accounts (not at all unlikely) would need to have ten unique, difficult passwords that he’d need to change twice a year. Some people have several times this number of accounts. The burden on memory, or likelihood of forgetting a password, becomes unacceptable.

4. A password manager is great, but if the user forgets the master password, he’s out of luck. Also, it is not impossible for someone to crack the master password, giving him every password.

I suggest that a person go ahead and write down all his passwords. Instead of sticking this list on his computer, he can put it in his wallet. Maybe he could place a copy in another safe place, in case something happens to his wallet. This way, his passwords would be as safe as his credit cards or his cash. If he is clever he might do a bit of scrambling to make it less obvious that it’s a list of passwords.

23 Smitha GS December 20, 2011 at 5:23 am

All your tips are very useful. For a beginner like me, its a boon from the God Himself :)

24 dingo March 7, 2012 at 10:26 am

“Exempli gratia” means “for example”. So this “for e.g.” is like writing “for for example”.

25 Zalmoksis March 27, 2012 at 5:59 am

What is a stronger password?
*eight random characters like “oDF4#f9s”
or
* a sentence like: “Pink unicorn swims in a river of milk.”

26 Randy Spydell March 27, 2012 at 1:08 pm

Baruch, I disagree that better passwords are harder to remember. See Zalmoksis’ comment about Pink unicorns’ swimming habits. And writing them down and storing that written list anywhere but a darn safe place (home safe or bank safety deposit box) is not a good idea.

I can think of many passphrases that are not that hard to remember and pretty darn hard to crack, e.g.
1. SummerStarts_Jun21-most0theTIME
2. It-was_34below=2005Dec08
3. SendMomACard-everySep25AnnUAlly
and the hint phrases can be easy to remind and hard to decipher, for the above three:
1. begin long day season
2. weather event first month of new job
3. maternal love duty each year
Because each hint is something that points me in the right direction, even if I don’t use the passphrase for weeks or months, the hint reminds me of which phrase it is.

When I gave talks to university parents about encouraging their students to be secure and use long passphrases, I ended the discussion by pointedly addressing the dads in the audience, suggesting they adopt long passphrases for their own accounts. Then I write on the board the following, “ImarriedSusan_15-Jun-1984″ and suggested that was a passphrase they’d NEVER forget and had multiple characters from each of the four character classes. That usually evoked laughter from the dads AND the moms. Point made.

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