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Master Lock Combination Recovery

Master lock combination recovery
It’s not hard to recover the combination to a combination lock. With three numbers ranging from 0 to 39 there are 64,000 possible combinations and attempting to brute force a solution at 10 seconds per try could take 22 days of non-stop testing. With this technique it will take only 15 minutes without any experience. After you’re successful, it takes less than 10 minutes to crack the combination. I’ve even included a program that will help narrow down the possibilities and make the process quick and painless.

This procedure was designed for Master Lock brand combination locks new and old. The illustration shown to the right illustrates the “slop” in the mechanics of the lock. A combination of 22-10-17 is the same as 22-11-17 or 22-9-17. This makes Master Lock combination recovery a lot easier.

Step 1. Make a list of possible last numbers of the combination.

  • Turn the dial clockwise past zero three times and leave it set to zero.
  • Apply even tension to the metal shackle (U-shaped part) by pulling down if it’s attached to something or pulling up if you’re holding it in your hand. This causes the dial to stick and not turn easily. So, apply just enough tension and turn the dial clockwise until it stops. Note whether it stops right on a number or between two numbers. While still applying tension turn the dial counter-clockwise (left) to find the range.
  • If the range is between two numbers say 17 and 18, record the number as 17.5. If, on the other hand, the range is in the middle of two numbers, say 20.5 and 21.5 record the number as 21. This is the middle of the range. You can rest between numbers; it won’t affect the solution.
  • You can release some tension from the shackle to get past the sticking point to find the next sticking point. Repeat this process until you get to zero.
    HINT: The dial should stick every 3-4 numbers.

Step 2. Find the last number of the combination.

In one complete turn of the dial you should have 12 numbers recorded. 7 of the numbers should be fractions ending in .5 – these can be eliminated. Of the remaining 5 the last number in the combination is the whole number with the unique ending. For example, with my test lock I listed the following numbers:
38, 34.5, 31, 27.5, 24.5, 21, 17.5, 14.5, 11, 7.5, 4.5, 1. removing the fractions and the similar numbers ending in 1 leaves 38, the only number ending in something other than 1.

Step 3. Calculate the possible combinations.

Select the number you found in Step 2 into the Combination Calculator. It will calculate all the possible combinations, 64 in total, much fewer than 64,000, and it usually takes, on average, only 32 tries to find the correct combination.

Hint: And in case you forgot, it’s always twice past zero turning clockwise (right) to the first number, once past zero to the second number counter-clockwise (left), and finally clockwise (right again) to the last number.

Good Luck.

Discussion

122 Responses to “Master Lock Combination Recovery”

  1. This is a brilliant site, to be sure, but now it’s clear who stole Pee Wee’s bike.

    Come to think of it, I’m missing some underwear from my locker at the gym. You wouldn’t happen to know the whereabouts of a certain black lace thong, would you?

    Posted by Vegas Linda Lou | June 10, 2009, 7:29 AM
    • When I was a young teen, I bought a 3 speed bike with my own money. While at ta park, I locked it to a tree. When I returned, the lock was gone, but the bike was still there. I thought it was some wise ass kid that did it, now I know that it was a brillant adult like you practicing. Thanks for clearing that up! I am going to send my son to this site!

      Posted by Lori Biker | June 11, 2009, 10:48 AM
    • Once said, “knowledge is a form of power” but really this upsets you? A theif will take a hammer & smash part of the lock or use a cloth, well… Thank you, now I can use that old lock I have again. Something about keeping honest people, honest. Ching Chow..

      Posted by Rude Awakening | July 25, 2009, 9:34 PM
  2. Clearly there is a hidden culture that frequents web sites like this. Now you two have joined that culture. Linda, what have you done?

    Posted by Russ B | June 12, 2009, 7:08 AM
  3. This is great. I’m going to try this. I have a lock that I lost the combination for, although I remember one (maybe even two) of the numbers. This will help me to be able to get the combo quickly.

    Posted by imshakinmyhead | June 16, 2009, 10:53 PM
  4. Worked for me:-)

    Posted by Random Electron | July 5, 2009, 1:31 PM
  5. Worked for me, too! you don’t have to do all that stuff for the last number; pull down hard and turn; dial will lock up firm on the last number. Then go to Calculator. Start with the more likely groups (different first and last numbers. I did it in 19 trys. :)

    Posted by Ro Efa | July 21, 2009, 7:42 PM
    • Please not that two of the numbers can be the same. I read on various website that this is not the case and it was giving up on cracking my old lock, but thought I’ll give it a try and my combination turned out to be 26-32-26.

      Posted by Anna | August 16, 2011, 1:32 PM
  6. Doesn’t work for Hardened locks. How about a tutorial for them?

    Posted by secret agent girl | July 28, 2009, 5:14 AM
  7. what is the algo used to eliminate the band of numbers going diagonally?

    Posted by c0rm3n | August 27, 2009, 11:44 PM
    • The mechanics of these locks are sloppy enough that adjacent numbers are valid combinations. For example, a combination of 9-27-12 is the same as 10-27-12.

      I have posted the source code for your perusal. Does this answer your question?

      Source code in PHP

      Posted by Mike | August 29, 2009, 2:46 AM
    • “what is the algo used to eliminate the band of numbers going diagonally?”

      Posted by c0rm3n | August 27, 2009, 11:44 pm

      What happens is that sequential numbers which are close together are eliminated. This is because the design of these combo locks gives fairly large tolerances when entering a combination. It seems to be plus or minus 1 number giving you a range of about 3. Because of this, the possible combinations cannot contain sequential numbers that are only 2 values apart.

      A combination of 10-12-26 would be invalid because once you enter the 10, the 12 will just fall into place, making the entry of the combination very awkward and difficult.

      A combination of 10-32-34 would also be invalid for the same reason, even though the two numbers that are too close are the second and third. This flaw exist across the entire combination.

      The algo that eliminates the diagonal numbers simply looks at the first two numbers in the combination and if they are only two numbers apart, that combination is eliminated.

      This is the same reason why there is a horizontal band of numbers missing. All of those combinations had second and third numbers that were only 2 numbers apart, and thus were invalid combinations.

      Posted by Tyler Roussos | October 18, 2009, 10:20 PM
    • Here’s exactly how those other numbers are eliminated. There are two rules that cut the possible combos from 100 to 64:

      Rule 1: The second number cannot be 2 more or 2 less than the third number.

      Ex: Combos that wouldn’t work:
      2-36-34 | 36 is 2 more than 34.
      2-32-34 | 32 is 2 less than 34.
      22-0-38 | 0 is 2 “more” than 38.
      22-0-2 | 0 is 2 less than 2.

      Rule 2: The first number cannot be 2 or 6 more than the second number.

      Ex: Combos that wouldn’t work:
      18-16-34 | 18 is 2 more than 16
      18-12-34 | 18 is 6 more than 12
      0-38-4 | 0 is 2 “more” than 38
      0-34-4 | 0 is 6 “more” than 34

      Keep in mind, those zeros are can be sneaky little bastards! Remember that you’re dealing with a wheel here.

      If you follow these rules, you can crack the combo without a computer! You may need some extra paper though, at least if you’re like me and need to write all the combos out. :D

      Posted by Chuckles | June 8, 2010, 2:26 PM
  8. thank you very much for this, I’ve been trying for hours to figure my combination out when I finally decided to look up help. surprisingly enough, the combination was the first on the chart (:

    Posted by Jostie | September 9, 2009, 2:39 AM
  9. In responce to hardened lock question ..I had a hardened lock that this method didn’t work for because all of my whole numbers ended in 4. I looked for the loosest one and began trying on them and it did open. So look for the loosest whole number to get your last number.

    Posted by No Profile | September 21, 2009, 7:00 PM
    • ^^ FTW! I had 4 0′s and no other whole numbers, the loosest one was the third number.

      Posted by Hardened lock | October 8, 2009, 10:00 AM
    • Wow, I wish I’d read this earlier. I convinced myself that a couple of the half numbers were possibly whole… now my hands are numb from all the futility, but at least I’ve got it!

      Huh, my last number was also 30.

      Posted by David | December 5, 2010, 9:09 PM
    • I love you so much right now. I had 4 whole numbers, and 8 half numbers. I was trying to figure out which of my halves was wrong for soooo long before I saw your comment. I have a hardened lock also. Btw, my last and loosest number was also 30.

      Posted by Grateful | January 20, 2011, 9:31 PM
  10. It works. Most of my numbers stop between numbers, not on a number. So it was a little tricky. The last number for me, which is 6, actually stopped between 5 and 7. I did remember my combination had a 6 or a 2 in it so it took me only 3 tries to figure out from there.

    Posted by Rina | October 5, 2009, 6:46 AM
  11. It was very hard for me to get the last number but I did find my combination. THANK YOU!!

    Posted by jmaya | October 8, 2009, 6:47 PM
  12. c0rm3n put it best when asking:

    “what is the algo used to eliminate the band of numbers going diagonally?”

    Posted by c0rm3n | August 27, 2009, 11:44 pm

    I’m not into reading code (and not for lack of trying. Specifically the source you provided.)

    The “long” method popularized on all the other websites instructs composing the list of 100 possible first and middle numbers. In the field, I’ve tried a few that I suspected couldn’t work after trying them because of the awkward placement of certain number pairs and the mechanical feeling that the dial “went too far in the other direction.”

    What is the layman’s-written-out-in-plain-language mathematical process for narrowing down this list to 72 as I understand it to do? What is the criteria for eliminating some of the numbers off the bloated “100 list?”

    By the way, awesome site and helpful contribution!

    Posted by tester | October 16, 2009, 7:59 PM
  13. I can’t believe that it actually worked. When the shackle came unlocked, I sat there staring at it in disbelief. So I tried it again and it worked. thanks a lot again. I will be referring back to this site for all my master lock combination needs. Oh, and by the way, it does work for hardened locks.

    Posted by THNKS | October 22, 2009, 7:58 AM
  14. Didn’t work for me but will try again.

    Posted by LockedUp | October 25, 2009, 1:37 PM
  15. There’s also a new iPhone App ‘LockGenie’ which helps with this and gives you extra mobility.
    http://itunes.com/apps/lockgenie

    Posted by Josh Kessler | October 27, 2009, 3:29 AM
  16. The computer calculated combination sets generated for “last number” 29 do not give the combination 15 20 29- which is what my 800XXXX MASTER is??? Luckily I found the original leaflet and combination that came with my lock!! (after going aroundandaroundandaround…)

    Posted by 5n0wf1ak3 | October 27, 2009, 11:48 PM
    • My guess is the last number of 28 will open this lock. When the last number is odd I always take the lower even number to make this work.

      You have brought up a good point concerning ending odd numbers and I will investigate further.

      Posted by Mike | October 28, 2009, 12:50 PM
      • This method worked great for the first lock I tried but the second lock have a last odd number and I am having no luck. I tried all the combo’s on the chart twice and then read your post. I rounded down to 30 from 31 and recalculated the chart and tried all those numbers with no luck. A couple of questions:
        1) do you mean to round down and then recalculate the chart? or calculate the chart with the odd last number and then round down just that number from each of the chart numbers?
        2) When spinning the combo, pass 0 twice first spin clockwise, pass 0 once counter-clockwise second turn.
        I had a line of combo’s from the chart with 0 in the middle. I tried both landing on 0 the second turn and passing zero twice and landing on the third zero. Which is correct?

        Thanks for the great info!!

        Posted by amden | December 21, 2009, 12:49 PM
  17. I’ve been trying to figure out my combo for two days by doing this method with my own math. Finally I found your chart and I got it open! (Of course my combo was the second to last on the list…) Needless to say I have sore fingers.

    Posted by faith | November 3, 2009, 6:21 PM
  18. This is way cool. I had a little trouble getting the feel of determining the last number. I had a false positive of the four numbers with the same last digit, which cost me some time. Then realized that I was had turned the dial counter-clockwise rather than clockwise to find the third number. I recall seeing another website that said clockwise, but it doesn’t matter. Just make sure that you turn the dial counter-clockwise to find the last number.

    Now that I’ve recovered my combo, it occurs to me that my lock is still as useless as it was when it was locked without the combo as are all my other Master combo locks. Anyone can crack these locks, so what’s the point of using them to secure anything of value.

    Has anyone seen a response from Master Lock regarding this flawed design. I didn’t see anything on their website. What a disappointment. I’ll never buy one of these locks again.

    Posted by Yul | November 21, 2009, 7:45 PM
  19. Wow. Just cracked the combo for 2 locks that were in cold storage. Thanks so much.

    Posted by Mark | December 13, 2009, 6:04 PM
  20. To clarify for the readers and what worked for me. The fractional numbers are the important numbers. Average the 5 fractional numbers. Once averaged, 4 of the 5 numbers will end with the same number. The one that is different is the last number of the combination lock. Then use the calculator.

    Posted by Trinopolyz | January 15, 2010, 5:25 PM
  21. I have a very old Master lock for a gym (the kind with a key slot in back and the combo dial on the front).

    My stepbrother would go around the school on the last couple of days and collect up all of these locks, from trashcans, from open lockers, you know what a jr. high school looks like at the end of the year.

    For fun, he would just go through the combos from the start 0-0-0 and find the combo. He got good at it, I mean REALLY good he could pick up a cold lock and in 5 to 10 minutes it was open. I think his brain got the algorithm in his head.

    At any rate, he always had a box of locks if anyone needed one. He gave me one and it has been really beat up, dented, misused, and abused. The combination for it is 0-10-0.

    I had forgotten the combo. So I tried the long way and it wouldn’t give five whole numbers, it always gives six, after playing around with it for the weekend I still can’t open it, should I just junk it or is there a trick of some sort? I got the lock in 1973. It don’t owe me now’t, but I don’t want to throw something away if it will work.

    Posted by Jay | January 17, 2010, 11:08 PM
  22. Thank you so much for this post! I just cracked a combo for a lock that’s been stuck on a bag for 5 years!!

    Posted by Kimberley Foreman | January 18, 2010, 12:06 PM
  23. Thanks to all of you for your posts. My lock had 8 fractional and 4 whole numbers. After trying the fractionals as possible last numbers, I re-read the posts more closely. I looked for the loosest whole number which was the first 8 in the series of 8s. I also noticed through all this trial and error, when the shackle was pulled up, my lock would click (hit metal) consistently clockwise on 14 and counterclockwise on 12. For kicks, I went through the combos with 14 as the middle number and found the combo of 32-14-8. For anyone looking for serial number 905460, this is the combo.

    Posted by I got It! | January 19, 2010, 10:06 PM
  24. Thank you. Thank You. THANK YOU! I recovered the combination to a Master Lock lock that I have owned since high school (I’m now a grandfather), but could not open.

    Posted by Darden Cavalcade | February 21, 2010, 1:03 PM
  25. I have tried this about 30 times. I also have had other people try it. We all come up with the same numbers. 0, 3.5, 6.5, 10, 13.5, 16.5, 20, 23.5, 26.5, 30, 34.5, 36.5. I can only get 4 whole numbers and they all have the same last digit. Any suggestions on how to get the combination?

    Posted by Rachel Brogdon | February 22, 2010, 7:12 PM
  26. You Rock!

    This helped me solve a pad lock my dad forgot the code to in boot camp 19 years Ago!

    Posted by Jake Self | February 27, 2010, 12:20 AM
  27. This was amazing. After looking at the possible combinations, I got it in one try!

    Posted by Petey | February 28, 2010, 12:32 PM
  28. It didn’t work on my MasterLock model 1504 (purchased on 2009). Apparently this model uses another algorithm

    Posted by Zeva | March 4, 2010, 7:19 AM
  29. Totally Works… had 2 locks collecting dust for over 5 years in my drawer and finally founds their combination with this trick… thanks a lot!

    Posted by Mike Gaum | March 31, 2010, 7:48 PM
  30. I only get 10 sticking point ranges on an American lock. 4, 12, 36 are the only whole numbers. It seems like this should be an easier algorithm, no? Any ideas?

    Posted by ERic | April 3, 2010, 2:49 PM
  31. I originally learned this back in 1964. It was shown to be by an Eighth grader. He could actually open one in less than 10 seconds is looking at the lock and about 30 seconds behind his back. I since forgot quite how to do it so I decided to look online and here it was. There is another way to crack the lock if the lock is not on something and that is throw it down hard on its shackle, it sometimes will snap open. This does not destroy the lock, but you still wont have the combo.

    Posted by J | April 3, 2010, 3:42 PM
  32. Not sure what to do. I had 2 locks that I bought at the same time, and their serials are close together. I was able to use this method to open one, but there’s no clear solution to the other. I’ve gone over the sticking points about 6 times.

    1.5, 4.5, 8, 11.5, 14.5, 18, 21.5, 24.5, 28, 31.5, 34.5, 38

    That makes only 4 whole-numbers (8, 18, 28, 38).

    Any ideas??

    Posted by John T | June 11, 2010, 11:06 AM
    • I had the same problem. What seemed to make sense, was that the “sloppiest” whole number was the ending number. If you don’f feel like testing all of them again, then write down the ranges instead of the average each time. My last turned out to be 6, with a range of 5 – 7. Whereas the other whole numbers had ranges of 35.5 – 36.5. Hope that helps!

      Posted by Matt | August 12, 2011, 11:32 PM
  33. Does this work for built in locks with numbers from 0-49 instead of 0-39

    Posted by matt | June 20, 2010, 8:49 AM
  34. Awesome! Masterlock’s web site wants you to fill out a form, photocopy your lock, get the form Notarized, and mail it in for a 4-6 week turnaround. I’ve had this lock for years and finally lost the little code sticker that came with it. I had a vague memory of the code, and that the first and third numbers were similar. I ran through the dial twice to get the list of possible numbers, found the most likely last number (I ended up with 4 and relied on my memory), and got it open on the first try. THANK YOU!!! Now, do I bother using this for the lockerroom because it was so easy to crack? …yea… My clothes aren’t that valuable! woo hoo!

    Posted by very pleased | June 27, 2010, 2:54 PM
  35. Doesn’t work for me. I get six .5′s and six whole numbers:
    39, 36, 29, 19, 16, 9. Four 9′s and two 6′s. Any ideas?

    Posted by Branden Wolner | June 29, 2010, 1:40 PM
    • OK. So I had four 9′s and 2 6′s. I picked one of the two 6′s and started there. Sure enough, it was the correct final number and I got the lock open. I guess if I had tried all 64 I would have then tried the other 6 as the final number.

      So, FYI for others who have this problem. Try both of the two “unique” ending numbers.

      Posted by Branden Wolner | June 29, 2010, 2:13 PM
  36. Wow … it really works. I have a master lock from high school sitting around in a toolbox for 25 year. I mixed some of the number up the first time, but got it straight the second time and found the last number was ’8′ … printed out the list of possible combinations … picked a column that looked right and bingo! opened up on the very first try. Amazing. Thanks!

    Posted by Will | July 4, 2010, 3:04 PM
  37. got lucky! 1st try woohoo!!! yyeaahh! i tried soo many sites but this is the only 1 that worked 4 me i think it is great!!!!and now i dont have to blow a ton of money (well kind of a ton) on a new lock! you go girl (or guy, idk) :)

    Posted by Hotshot | July 13, 2010, 6:58 PM
  38. Thanks, this worked great. I got the list of 64 combos and recognized what the combo was. So I got it on the first try. :) Lucky me!!

    Posted by Rick Davis | July 14, 2010, 8:26 AM
  39. I got twelve numbers, but five are .5s and seven are whole. All the .5s end in the same number except for one, which, using the method described above for the .5s instead of the whole numbers would give me a last number of 1.5. That doesn’t work with the math unless I treat it as either a two or a one, and that leaves me with twice as many combinations to try. Any other options?

    Posted by shoelace203 | August 13, 2010, 6:46 PM
    • UPDATE: I exhausted all possibilities for 1 and 2 as the third number with no luck. 8.5 is the loosest of the stopping points, but, once again, I’ve got a fraction instead of a whole number. I guess I’ll try 8 and 9 but I’m wondering if I read the stopping points as the wrong numbers.

      Posted by shoelace203 | August 14, 2010, 10:51 PM
  40. Thank you so much. Because of this, I was able to open my High School lock from ’91 and give it to my daughter to use for one of her school lockers!

    Posted by Mike Pflugfelder | October 5, 2010, 6:47 PM
  41. Nice. Got it on the 13th attempt. (I worked the possible combinations list backwards) The hardest step was finding the stopping points. I’ve tried this on 2 other locks now, that I did know the combination to, and it worked. Thanks.

    Posted by Greg | November 3, 2010, 2:36 AM
  42. The problem that some of you may be having with the hardened locks is that Masterlock changed their tumbler design for a lot of the locks that have serial numbers beginning with 800. If you check the wikihow article on how to crack a combo lock, it gives some tips as to what might be going wrong if this applies to your lock.

    Posted by SamRaven2 | November 22, 2010, 5:52 AM
  43. Tried on on a Hardened Masterlock serial 911*** and it worked just dandy. Takes a bit to figure out the whole tension / wiggle technique so you get the right numbers but it worked for me.

    Posted by Mike | November 30, 2010, 5:09 PM
  44. I just tried this on a Sphero serial 8000xxx, and none of the combinations worked. My last number is 37. At first, on my first try with 1-3-37, the shackle popped open, but ever since, I haven’t been able to open it with any of the other combos. Any ideas?

    Posted by Nathan | December 7, 2010, 12:20 AM
  45. Got it in the FIRST tried it worked! :) and i hadn’t used my lock in almost a year i had no idea what the combination was

    Posted by Jolly | January 14, 2011, 1:11 PM
  46. well, it may have worked for you, but i only got the first two digits, leaving me with so many others, oh well, i guess i got work to do…

    Posted by xpert | February 20, 2011, 11:20 AM
    • Some times the sticking points for finding the 3rd number are not exactly on top of a number or between two numbers. In this case:
      1. turn clockwise (right) the first of the 12 sticking points from 0
      2. continue to turn clockwise to the opposite side of the dial
      3. turn counterclockwise (left) back to the first sticking point from 0
      4. pull up on the lock and turn the dial left and right in the small sticking area and write down the exact range. (e.g. 2.75-3.5)
      5. repeat this 4 more times for the numbers 10 more from each other. (e.g. 3, 13, 23, 33)
      6. now do steps 1-5 for the second sticking point past zero
      7. do the steps again for the third point past zero.

      Posted by Mike | February 20, 2011, 1:41 PM
  47. Another interesting characteristic of Master Locks….

    Each lock has TWO combinations — they are different and determined by which direction one turns the dial to start the process. Sometimes the alternate combination only has two numbers.

    Posted by nate | March 2, 2011, 4:30 PM
  48. I just opened a lock I used on a high school locker 6 years ago- it’s great!

    However, at the bottom of the article is the note about moving past 0 for each number; this is somewhat incorrect. The number to pass is not necessarily 0, but the next number in the sequence. For instance 26-04-14, to go correctly from 26 to 4, I pass 0 twice and 4 once, stopping the second time around. Then passing 0 once and stopping on 14 for the final number.

    Posted by mj | May 30, 2011, 10:48 AM
  49. Hi Mike,

    I like your information on locks.

    I also have some information on master combination locks.

    I have a video at:
    http://www.metacafe.com/watch/862947/find_forgotten_combo/

    You can easily get the combination to a lock (if it is open already).

    To get it open, you can make a shim from a soda can.

    Scott

    Posted by Scott Murphy | July 16, 2011, 4:09 PM
  50. I did it, too on a 900 series. I had that thing for over 35 years since high school. In fact I have 2. One I had the combo for and the other I just cracked. Once I had the list of possible combos, I tried several of the last ones. Then a few I sort of recalled. Then I guessed another and it opened. The last number is NOT the one I always recalled but the method (after doing like 5 times) told me it had to be it. It work. Now I am going to try it on any others I may find or pick up at the swap meet or garage sale. I actually have a use for these things, too. Yes you can crack but seriously you have to be really after my yard tools to do it! THANKS!

    Posted by Walt | August 10, 2011, 12:22 PM
  51. This is a great resource! Worked first time – saved me $10 for a new lock – Thanks!

    Posted by crlf | August 19, 2011, 2:11 PM
    • This method does work; however, the 3rd bullet in step 1 should say, “. . . If, on the other hand, the range is in the middle of two numbers say 20.5-21.5, then record 21!, not 20, because 21 is the middle of this range.” Otherwise your whole numbers will always be one number too low! This worked for me . . .

      Posted by NLeone | January 21, 2013, 5:15 AM
  52. My combination is 31-36-9.
    If I were to try this method it would be impossible to find the combination to my lock

    Posted by venus | August 24, 2011, 12:08 PM
  53. Awesome worked for me thanks

    Posted by ONE | August 24, 2011, 9:37 PM
  54. It worked!! Thank you so much!! I’ve been racking my brain for weeks on the combo to this lock…

    Posted by C | August 27, 2011, 3:14 PM
  55. For some reason I get 4 whole numbers and 8 fractions. Is that possible?

    Posted by Confused | August 29, 2011, 9:44 AM
  56. Fantastic! I have a lock I hadn’t used for a couple of years and couldn’t remember the combination for the life of me. Once I figured out the last number and looked at the possibilities, the combination jumped right out at me!

    Posted by Angie | August 31, 2011, 4:21 AM
  57. This is so cool! My new school locker had a lock on it already and I was able to remove it and put on my lock using your technique. The custodian was amazed and said he will use this all the time instead of cutting off a lock. Thanks!!!!

    Posted by Critter | September 1, 2011, 10:55 AM
  58. This works. Very cool!

    Posted by m | September 7, 2011, 7:22 PM
  59. Worked great. Thanks for the technique and the combination calculator.

    Posted by John | September 30, 2011, 8:32 PM
  60. i have been trying this method for my lock, but for the first step, the whole numbers left all end in either 6 or 9. what am i doing wrong?

    Posted by amy | October 19, 2011, 1:48 PM
    • Two points. Make sure you’re turning the dial clockwise and try try to apply a little less tension on the lock. It sounds like the 6 and 9 ending numbers can be ignored.

      Hope this helps!

      Posted by Greg | October 19, 2011, 9:55 PM
  61. Beautiful! Worked like a charm! Thanks!

    Posted by Mike | November 8, 2011, 3:05 PM
  62. That is the most AWESOME thing. Thanks!

    Posted by Nina | November 12, 2011, 6:55 AM
  63. The numbers it gave me were
    37,34.5,31,27.5,24.5,20,17.5,14.5,10,7,4.5,0

    So this should mean that it ends in 31 right?

    Posted by Josh | December 10, 2011, 10:48 PM
  64. i have tried to find the ending number 5 times by they all end in 2.5, 6, or 9 what am i doing wrong?

    Posted by frustrated | December 12, 2011, 6:54 PM
  65. I have actually tried this method twice, but I can’t seem to tell if the first set of numbers is a .5 or not. I give up. The lock is an old pink/purple masterlock. :?

    Posted by Tim | December 14, 2011, 10:11 PM
  66. You sir are a genius…got it to work in 15 trie

    Posted by Frustrated Guy | February 9, 2012, 7:33 AM
  67. Mines not working… any extra tips? how many tries does it typically take?

    Posted by Itsss nott workng :( | February 12, 2012, 12:15 PM
  68. hot damn it works
    took me a while

    Posted by zillfat | February 17, 2012, 2:46 PM
  69. i need more locked locks.

    Posted by zillfat | February 17, 2012, 2:58 PM
  70. Found a lock in my closet, haven’t used it in YEARS….used your system….within 1 hour I was able to pop the lock open…Pretty cool!

    Posted by JW | September 13, 2012, 12:58 PM
  71. What is the algorithm in your calculator?

    How are you determining the first two number possibilities?

    Posted by Calvin | March 2, 2013, 2:37 PM
  72. I KNOW THE FIRST AND LAST NUMBER WHICH ARE BOTH 27. HOW DO I FIND THE MIDDLE NUMBER. NOT A MATH WIZ. I DO KNOW IT’S NOT FAR FROM THE 27, BUT I JUST CAN’T REMEMBER IT. THANKS.

    Posted by StarBird | March 2, 2013, 7:48 PM
  73. Hi, can you please help me with this, I believe I have a unique situation here. At the end I get numbers 6, 16, 26, 36. Which one is the number I should choose?

    Posted by JoPrez | April 25, 2013, 3:32 AM
  74. I had a Masterlock that I took from my brother when he came home from Navy boot camp in 1964. I’ve kept it all these years and I never knew what the combo was. Using this method, I got it open in 10 minutes. I should have started on the other end of the page, there were only 5 combinations left when I hit the right one.

    Posted by Brady | May 14, 2013, 11:29 AM
  75. AWESOME!!!! now to find all those old locks. LOL

    Posted by Lu | June 1, 2013, 9:55 AM
  76. I have an old lock that I’ve not used in some time. The only number that I vaguely remembered being in the combo was 35. After I figured out the last number and put it into the calculator, I tried the first few in the list and then went straight to the ones with 35. I found the combo within six tries! It’s unbelievable that this actually works. Thanks for the clear instructions on how to recover the combo.

    Posted by Mark | June 2, 2013, 3:16 PM
  77. My number: 38, 35,31.5,28,24.5,21.5,18,14.5,11.5,8,4.5,1.5
    Clearly, my last number is 35, but I tried all combination, not anyone works. Need urgent help please!

    Posted by Jacky | June 4, 2013, 10:15 PM
    • Hi Jacky,
      You may want to try running the calculator for the last number as 34 and if that doesn’t work try 36. This has worked for me with the newer locks. Good luck!

      Posted by Mike | June 5, 2013, 1:10 AM
  78. Can’t believe this worked. I went through the process of finding the 12 numbers a few times just to make sure there were no descrepincies and BOOM… Got my lock undone. Who ever developed this and the calculated… Hats off, and a huge thank you.

    Posted by Mike | June 12, 2013, 6:37 AM
  79. After the last number is found, there should be 10 possible choices for the first number and 10 for the 2nd. That would yield 100 possible combinations. How did you wittle it down to 8 x 8 = 64? Thank you.

    Posted by Stan | June 28, 2013, 6:40 AM
  80. After reading other comments it seems a few other people have the same problem I have. My numbers are 2.5,6,9,12.5,16,19,22.5,26,29, 32.5,36 and 39. I’ve used this method on other locks and it worked but I can’t figure this one out. Anyone else figure this out?

    Posted by Jeff | July 20, 2013, 1:55 AM
    • 6 was my third number. After checking the numbers again I realized that the range of motion was slightly greater at 6 than at 16, 26, and 36. If anyone else is having the same problem check your numbers again if one of the four #’s ending in 6 or the four #’s ending in 9 move slightly more to the left or right than the other three #’s this could be your third number. You really have to look close because there was only a very little difference in my case. Worst case scenario try all 8 whole numbers as your third number. This could take some time though. I also read somewhere that you can eliminate two out the ten second numbers (2 numbers above and 2 numbers below whatever your 3rd number is). This narrows down the posible combinations from 100 to 80. I hope this helps.

      Posted by Jeff | July 20, 2013, 6:49 PM
  81. I had a similar problem. I kept trying but couldn’t get it until someone suggested turning the dial counter-clockwise. It worked like a charm.

    Good Luck, hope this helps you.

    Posted by Jason | July 20, 2013, 4:16 PM
  82. I started on another site and could not figure out what the last number was. I kept getting 3 numbers ending in 9 and 2 numbers ending in 6 (39, 35.5, 32.5, 29, 25.5, 22.5, 19, 16, 12.5, 9.5, 6, 2.5). I read thru the posts and found 2 answers that helped:
    1. Find the number with a little more range of motion than the rest. Normal range of motion was always really close to 1 except for number 6, which was between 5.5 and 7.
    2. I tried counter clockwise just to verify, same result, 5.5 to 7.
    I used the calculator specified on this site, and verified it against another at http://www.gliderspen.net/cgi-bin/masterlock.cgi, my combination was on both.

    Posted by Dave | July 21, 2013, 12:29 PM
  83. I have ran the possible combinations 4x, and double checked them the calculator. I still cannot get it open. Help!

    Posted by Angela Jacobson | August 5, 2013, 8:56 PM
  84. Help. I get five numbers: 9,16,19,36. What is my third number? Or what am I doing wrong?

    Posted by Kim | August 23, 2013, 11:06 PM
  85. Worked like a charm!
    Thanks!!!!

    Posted by Ed | August 28, 2013, 3:09 AM
  86. We bought a 2-pack with identical combination. We then proceeded to lose the combinaison. Hence my presence here.

    I’m unable to retrieve it as both lock have different sticky points:

    39, 35.5, 32.5, 29, 25.5, 22, 18.5/19, 15.5, 12.5, 9, 5.5, 2.5

    On this one, I tried 18 and 22 as the last number. Failed.

    36.5, 38, 30, 26.5, 23, 19.5, 16.5, 13.5?, 10, 6.5, 3.5, 0

    On this one, I tried and 23 and 38 as the last number. Failed again.

    The serial number are still sticked to the locks: 1500-05902.

    Posted by Martin Thomas | October 26, 2013, 9:18 AM
  87. I have tried this method several times , I always get 26 as the last number . I have tried every combo on the chart. But none seem to be the right one. I have checked and re checked but it does not seem to work for me.

    Numbers are : 2.5, 5.5 , 9, 12.5, 15.5, 19, 22.5, 26, 29, 32,5 , 35.5, 39

    Thank you

    Posted by Zoe | January 26, 2014, 10:13 AM
  88. Un-f*ing-believable! once I saw the list, I was able to pick out the right combo from memory. Open in a single try! Now I don’t need a new lock. thank you!!

    Posted by Liz | February 2, 2014, 12:54 PM
  89. I will be overjoyed if this works.

    Posted by Justin Chung | February 18, 2014, 4:05 PM
  90. Found an old Master Combo lock in a drawer and thought I would go online and try to crack it.
    Took me about 50 or so tries with the combination output sheet, but I finally got it!
    Mucho Thanks!

    Posted by Matto | April 7, 2014, 6:36 PM

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