How To: Crack and open a combination lock

Crack and open a combination lock

This video won't show you how to crack a safe but it will show you the next best thing: cracking a combination lock or master lock! We do recommend only trying this on a lock you have forgotten the combination to and not other unlawful purposes. Watch this video tutorial and learn how to retrieve the combination from a lock. Hack your own lock or your friends and you have the potential for great practical jokes.

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remember to only use thid method on your own lock, and not the one securing my bike. just use a bolt cutter. so much easier.

remember to only use this method on your own lock, and not the one securing my bike. just use a bolt cutter. so much easier.

in phase 2: the only possible remainders are 0,1,2,3 as stated. then after doin the whole 0,4,8,12...thing he uses remainders 0,1,3,4? i assume u meant subtract 2 from remainders 2 & 3??? or do u subtract 1 from them??? to get the numbers u came up w/?

this helped at the gym, but you do look suspicious

just smash it with a crowbar

dude you own my bike was locked up to a pole in my back yard and i couldnt remember the combination so when i tried this it worked easily but there is an easier way to do it with a soda can i can open combination locks and also key locks such as a master no.5 lock easily!

i tried this and it didn't work. RIP OFF!!

jimwang83 was right you said the only possible remainders were 0 1 2 3 but then in phase 3 u said add 3 to 0 and 1 and subtract 2 from 3 and 4 but we cant have a remainder of 4 as you said so wats up ??

still clapping


still clapping...




we had internet 100 years ago :o

just buy a new one and smash that one off

i dont get step 2 very well and i hope it works on this lock from school which i stole muahaha


great info, but this is why I carry bolt cutters in my truck.


does this work? someone reply?

if you have no remainder which would be zero would you always use the number 4

the last diget of my combo is .5 my number was 11 when i divided them i got 22 no remainder do i use the number 4 as my starting number?

Great Site

Didn't get how to do step one I got 9 numbers only

Thanks, I was able to unlock an old gym lock after the 58th combo.

Hi there, it is work but not all of them. If u see my comment let me know becuase I wanna learn more about it. Please thank's.

How do you open a forgotten combination of a "Realtor" push button lockbox?

OH NO, what if the remainder is a 2? You totally skipped it in step 3.

This narrator is awful because N3 mod 4 is 0, 1, 2, or 3, and he forgot about 2, but made up the case for 4, which already is covered by 0.

WikiHow has a better text explanation which further reduces the Trial & Error phase from 100 down to 80 cases, and includes exception handling for certain conditions not shown here.

This particular type of Master Lock is not good at all. Instead of having 64,000 possible combinations, it has only 3,200. A weakness yields its 3rd code, leaving an attacker only 10 and 8 values to test for the 1st and 2nd codes, respectively.

Lol I found the real topic on WikiHow it miss a lot of informations here!!

Look this dude just saved me gas for a trip to WalMart, probably 10 bucks, 'cause you gotta buy 'em in a 2pack, more crap for the landfill and his method works if you're not lame enough to give up. What the heck, now I can tell everybody I can get their combo lock combo it they need it.

Thanks for tutorial. What a gas!

P.S. I got mine to open in 4 tries. I don't use it to lock up my life savings, just for the gym locker. Who's going to sit on a locker bench with a pencil and paper and try to "math" it out just to get my smelly towel?

Hey this is a great way to figure out how to unlock a numerical combination lock. It really does work. I have used this technique before. But can you tell me how to figure out how to open a vintage post office box with Alpha combination lock? The lock contains letters A-J but I can't remember the combo to it. My grandmother gave this to me years ago and I've had it put up and my daughter found it and wants to use it but I can't remember the combo can you or anyone else out there help me Please? I know how to reset the lock but it has to be open to do this. I have tried everything I know to try and it's driving me crazy because I can't figure this out. Lol please help.

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