Most high school students with lockers know how to use a single-dial combination padlock because that's the type of lock most frequently supplied for lockers, and there's a good reason for that. There's no key to lose. All you have to do is remember three numbers and the correct dial sequence. You can also buy multi-dial locks for locking your bicycle or protecting the contents of your luggage. Multi-dial locks also use a three- or four-digit combination, and they're easier to open, but they're not as secure. In fact, compared to single-dial locks, they're ridiculously easy to crack.

Orange combination lock with silver padlocks
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How to Use a Combination Lock

You won't have to crack your lock at all if you remember the combination and write it down in a safe place. Master Lock, the number one supplier of single-dial locks, no longer imprints serial numbers on its locks, so its factory-set combinations are unrecoverable. You can reset the combination on multiple-dial locks, but that's no help if it's locked and you've forgotten the current combination.

How to Open a Combination Lock

The method for opening a standard combination lock hasn't changed since Master Lock introduced its first one in 1935. Just remember this sequence: "3-2-1 – Three to the right, twice to the left, once to the right."

Start by spinning the dial three or four times clockwise to clear it, then align the number 0 with the arrow. Turn the dial three times clockwise past the 0 and stop on the first number of the combination. Turn the dial counterclockwise twice past the 0 and stop on the second number of the combination. Finally, turn the dial clockwise directly to the third number and open the shackle.

The combination of a multiple-dial lock corresponds to the number position of each dial, starting from the one nearest the shackle. Simply rotate the dials until the proper combination lines up with the arrow, and open the lock.

Resetting the Combination

The combination on a single-dial lock is set at the factory and can't be altered. The procedure for resetting the combination on a multi-dial lock depends on the model. Manufactures may provide a reset tool, which is a thin metal bar that fits into an opening on the bottom of the lock or they may include a reset button on the lock. Some locks come with neither.

Just as you can't reset a password unless you know the current password, you can't reset a combination unless you know the current one. Set the dials to the current combination and follow one of these procedures:

  • Insert the reset tool into the aperture and turn it 90 degrees. Set the new combination, then turn the bar back to its original position and remove it.
  • Push in the reset button and keep it depressed while you set the new combination. Release the button when the combination has been set.
  • Open the shackle all the way, spin it through 90 degrees and push it down. If the shackle won't go down when you rotate it 90 degrees, try rotating it 180 degrees. Hold the shackle down while you set the combination, then release it.

I Forgot the Combination

Because single-dial lock combinations are factory set, you can only recover a forgotten combination by contacting the manufacturer. If your lock has a serial number, the manufacturer can match that number to the combination, although you'll have to supply a notarized form declaring you're the lock owner before you can get it. If the lock has no serial number, you're out of luck. You must either cut off the lock or pick it. Fortunately for you, the internet is full of instructional material for picking single-dial locks.

Because you can set the combination on a multi-dial lock yourself, the manufacturer can't help you if you forget it. The same two options apply: cut off the lock or pick it. It's even easier to pick a multi-dial lock than it is to pick a single-dial one. In fact, you can do it in less than a minute, following instructions available on YouTube and elsewhere.