2 Ways to Crack a Combination Padlock

Combination padlocks on lockers.

A combination padlock offers a challenge for anyone needing access to whatever it is they are protecting. A combination lock can be used to secure a fence, a box, a locker or just about anything that can be bound with a chain. If you lose or forget the combination, however, bypassing a combination lock can be quite easy. Read on to learn about the several ways you can remove or crack a combination padlock. Keep in mind that you should not use these methods for illegal purposes. If you have a combination lock that you need to be opened legitimately, call a locksmith.


Usually, the easiest way to get into a combination padlock is by using physics. Rather than using brute strength, there should be very little effort exerted on your part. You will require a vice in order to do this properly. Many people think that the weakest part of a combination lock is the latch, but this is actually the strongest area. It is solid metal and tempered. The weakest point on a combination padlock is the combination dial. This is typically made out of plastic. The side of this area is also where the combination padlock is put together.

Place the combination padlock between the vice jaws so that its ends are in the vice and not the front and back. Tighten the vice, putting pressure on the seam until it pops open.

Tension and Math

In the movies you'll see safe crackers using a stethoscope. What they are doing is listening to the ball bearings drop as they turn the dial. This method is not far from that method but all you need is a pen, paper, and a calculator.

Set the combination pad to 0 then pull up on the metal loop. Turn the combination pad until it stops then you record the number and release the hoop. Pull up on the loop and turn the dial until it stops again. Write down that number. Continue doing this until the combination dial reaches 0. If the number lands between two numbers use the lower plus a half. If it lands between 6 and 7 you would use 6.5 in your calculations. When finished you'll have 12 numbers: 5 whole numbers and 7 half numbers. Four out of five whole numbers end in the same digit. That's the third number in the combination. Divide this number by three and write down the remainder (0 to 3). Add four to the remainder and record the result. Repeat this until you have 10 numbers. One of these will be the first number in the combination.

Repeat the instructions, adding two to it. This will generate 10 possible numbers for the second number in the combination.

This will generate 100 possible combinations. Try each one until the lock opens.