Master Lock: All Possible 4 Letter Words

Master Lock has many different word combination locks and cable bike locks on the market that have fixed disks. (You cannot swap the order of the disks.)

In the escape room community, the three best known fixed-disk locks are:

Master Lock Model No. 1535DWD

Master Lock letter lock 1235DWD with the word "BOOK" appearing as the combination.

Master Lock Model No. 643DWD

Master Lock letter lock 643DWD with the word "MOCK" appearing as the combination.

Master Lock Model No. 175DWD

Master Lock letter lock 175DWD with the word "TEAR" appearing as the combination.

All of these fixed-disk letter locks have the exact same letter distribution, which made me wonder:

How many 4-letter words can these Master Locks create?

I hope to see more variation in solutions used on these locks in escape rooms. The same half-dozen words show up a whole lot. (I’m looking at you BURY, STAR, & SAND).

Three Master Lock letter locks with the combinations entered as sand, star, and bury.

Letter Distribution

Each fixed-disk letter Master Lock uses the following configuration:

Disk 1: L N B D M J P R S T

Disk 2: O U Y R T L H A E I

Disk 3: C D E O R S T L N A

Disk 4: K Y R S T L N E D H

What Words Can This Distribution Generate?

I asked Rich Bragg of ClueKeeper how he’d determine all the words these locks could generate. A few minutes later he sent me back a spreadsheet filled with words.

Column Explanation

There is no way to generate a single answer to the question “how many English words can this lock create?” English is a constantly evolving language. Words are created, usage shifts, and words fall into disuse.

Column A is the common English word list. This is by far the most useful column. It has 695 words.

Column B is the “ENABLE” word list. These are still words, but they are obscure or old English.

The next three columns are decreasing useful, with the fifth column being words from Wikipedia (which includes acronyms, initialisms and the like).

Each list omits the words found in the previous lists.

I’ve included all of the columns in the spreadsheet because even the less useful columns have some interesting entries… They are just few and far between.

Analysis Methodology

Bragg used TEA Crossword Helper, which is anagramming software on steroids. This is the kind of software that you use if you’re really serious about winning a major puzzle hunt.

From the TEA website:

“TEA comes with a database of over 6 million words and phrases including the title index for the English version of Wikipedia. These answers are classified by their familiarity, so you always see the most likely ones first. You can look up the meanings in the integrated dictionary/thesaurus or on the Internet. TEA is faster and more convenient than word lists in book form such as crossword completers, crossword dictionaries and crossword keys.”

Is There A Better Distribution?

The letters on each disk are pretty curious, especially when you notice oddities like the “J” in the first disk or the “Y” in the second disk.

From a letter frequency standpoint, these are not great letters to drop in those positions.

I reached out to Master Lock to ask how they chose this letter distribution, but they could not be reached for comment.

I suspect that there are more effective letter distributions possible that would generate even more words, but after a quick attempt at doing better, I fell a bit short. If you find one, I’d be curious to see it.

However, whether or not there is a better distribution, this is the one we have on these locks. It’s a lot of options. Feel free to use this list as a tool.

Master Lock Letter Lock Word List


  1. I LOVE that you have done this research and posted it! Thank you!! Have you done something similar for 5-letter locks? Are there other brands or models that give other possible combinations?

  2. Hi there! I’m a first grade teacher and do lots of escape rooms in my classroom using a lock box. I NEEDED this list!!!!! THANK YOU!!!!! 🙂

  3. This is just what I was looking for. Ive been trying to generate it myself using online tools but I cant find anything that works. MY only issue is that my letter disks have different letter. Would it be possible to generate a list off words with the new disks.

  4. My lock is pretty new. The words are formed vertically: these are the 4 disks:

    I don’t know the model

    1. I have same. Just bought.
      Package says flexible steel cable

      1. Same letter distribution in WordLock CL-422-BK. (I just bought one from Amazon, and apparently it was a return. Someone changed the default password (SHED) before returning it.) Trying to look for an alternative to trying out all 10,000 random letter possibilities.

  5. Here are the letters of mine. It´s a WordLock model TSA002. How do I find out the word combination possibilities? … Thanks.


    1. Can you please give me an Amazon link to the specific lock?

  6. I have a “MASTER” that will not open when I put the right combination of letters in. Can you help me unlock This lock?

    1. There are a lot of different master lock models and many different reasons why one might not open anymore. I’d need more details on model and what’s going on.

  7. Thank you for posting this and making the effort. I love reducing redundancy of effort and this did the trick!

  8. I noticed that a word I wanted to use could be spelt BACKWARDS with the 4 letter master lock. A list of common english words that could be spelt backwards would really open possibilities.

  9. Hi-

    We just bought a bike that has a letter lock on it. We are trying the different ways to force it open, but have thus far been unable to. I found your site and wonder if there is an algorithm that will give me all the possible words with the following letters:


    The discs are vertical, so disk 1 is SPHMTWDLFB, and so on.


    1. I think that I might have this one in the analysis pile. Can you tell me the model number?

    2. I have this same lock and forgot the combination! Did you ever find your list of possible words?

  10. HI I have a 4 letter wordlock padlock which I’ve just reset and forgotten the word I chose… (distracted by my children before writing it down) The disc offers the following letters disc 1) tglsbpdrhm, disc 2) eyaohurlni, disc 3) ernsaotcul, disc 4) blank ektladysn. Is there a way of finding out some common 4 letter words enabled by these discs?

    This is the product

    Many thanks,

  11. Is there a way for me to use a spreadsheet like this for my own bike lock?

    1. What model bike lock do you have?

      That said, I would not recommend using any letter lock to secure valuables. These locks are good for games, but are not adequate security devices. I’d urge you in the direction of something considerably beefier like this:

  12. Hi David, I’m looking for a word lock that spells ‘Navy’ and have been struggling. Do you know of any?


  13. I forgot my 4 letter word and can’t figure it out. HELP!

    1. There are methods for decoding a lock that you’ve forgotten the code for, but there is no easy way to solve this problem.

      The decoding (combination lock term for picking) method is to pull up hard on the shackle (the metal loop at the top), and then try each wheel, finding the tightest one, and twisting it until you can feel it hit a gate. This description isn’t going to be easy to follow if you’re unfamiliar with decoding locks.

  14. I’m trying to create a 4 letter word (LOVE) to unlock the lock. Couldn’t see any solution from the posts (no 3d printer) so I was wondering if anyone has modified the dial in the 3rd position by grinding off an existing letter and making a “V” even if crudely fashioned.

      1. Noo..
        Can I get some locks as I’ve designed?

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