A Step-by-Step Guide: How to Open A Master Lock 3 Digit Combination Lock?

Key Takeaway

  • To open a 3 dial combination lock, create enough tension on the shackles and then slowly rotate each number to figure out which number produces a clicking sound. 
  • Repeat the same process for all the 3 dials.
  • You may also use a shim to open a 3-digit combination lock without a code.

Whether you need to open a locker at school, the gym, or a suitcase, a combination lock offers an easy way to keep your belongings safe. But what about the situations when you can’t remember the code for the same?

After having accidentally locked my bag containing important documents and personal items, I was desperately searching for ways to open a 3-digit combination lock without the code. Since I was unable to find any reliable information online, I decided to try out different methods and document the entire process in an article for others facing similar problems. 

Thus, I wrote an article about how to open a 3-digit combination lock without the code by sharing step-by-step instructions along with helpful tips on making the process easier. 

What is a Combination Lock?

As the name suggests, a combination lock requires you to input a code to unlock it. The codes can be numbers, letters, or sometimes even images. The most common combination locks, however, unlock using a specific 3 or more-digit code.

A combination lock and a lever tumbler lock have the same principle of operation. The only distinction is that a lever tumbler lock uses a key to align the levers, whereas a combination lock uses a set of numbers for the same purpose.

What is a Combination Lock?

The lock’s lever is shaped like a hook and contains the latch and spring. The code needed to release the shackle must be entered into the lever in order to activate it. This mechanism is connected to the shaft, which then connects to combination wheels. The number of wheels on the lock corresponds with how many digits are included in the code. For example, there would be four wheels if a 4-digit combination was being used. 

Once the wheels have been set in their correct sequence, they will align and allow the lever to move, unlocking or locking your door as necessary.

Opening a combination lock whether it is 3 number or 4 number is pretty straightforward when the code is known but how do you crack it open when the code is not there? We will take a look at the step-by-step guide in the next section.

How To Open A 3 Digit Combination Lock Without The Code

In this section, we will take a look at 2 methods to unlock a 3 dial combination padlock when the code is not known.

3 dial master combination lock used for crack opening the code

Cracking The Code By Creating Tension On the Shackle

Opening a 3-digit combination lock without the code can be done by creating tension on the shackle while attempting to crack the code. 

Since I use Master lock 3 dial combination lock, I have tested these instructions on that. But the principle will work for cracking any 3 digit combination lock.

  • Step 1: To start, hold the combination lock so that the shackle (the metal loop) is pointing up. You will need to create tension on the shackle in order to open the lock.
  • Step 2: Pass a length of rope through the shackle of the lock and tug it tight. Doing so will generate friction among the lock wheels, which will then cause a clicking sound to be heard when they are adjusted. You can also use other means to apply tension. I did it with my fingers. This sound can indicate the right position of the wheel, and the code can then be deciphered.
Applying tension on shackles of the 3 dial combination lock
  • Step 3: Then, turn all the wheels on the lock to identify the most difficult wheel to move. This will give you an indication of where to start when trying to break the code.
  • Step 4: Identify the most stubborn dial and rotate it while the shackle is raised. Listen for a ‘click’ and feel a slight lift of the shackle. Repeat this action a few times to confirm that the wheel always clicks at the same number. Record this figure since it is most likely the one for that particular wheel.

    This will indicate that the tumbler has found its first number.
  • Step 5: Without releasing the tension on the shackle, rotate the second hard-to-turn dial until you hear a clicking sound. This will be the second number.
  • Step 6: Now, repeat the process with the third dial. This should be the third and final number. 
  • Step 7: When you have all three numbers lined up, push down on the shackle, and the lock should open. 
Cracking the code on Master Lock 3 Digit Combination lock

If you have difficulty finding all three numbers, repeat the steps above and pay extra attention to when you hear a clicking sound and when the shackle stops spinning clockwise. This method of cracking the code may take some time and patience, but it can be a great way to unlock a combination lock without knowing the code.

Using a Shim To Open A Combination Lock

Using a Shim To Open A Combination Lock

Shimming is a great way to unlock a combination lock without knowing the code. It’s relatively easy and doesn’t require any special tools, though some practice is recommended. Here’s how you can do it:

  • Step 1: Start by inserting a shim (a thin piece of metal) into the top or bottom of the lock, between the body and the shackle. This will create tension on the shackle and make it easier to manipulate the lock.
  • Step 2: Now, while holding the shim in place, use your other hand to turn the dial clockwise and counterclockwise. You’ll feel the shackle move slightly each time you turn the dial.
    holding the shim
  • Step 3: Continue turning the dial until you find a point where the tension on the shackle disappears. This means that the lock has been released and is now open.
  • Step 4: Carefully remove the shim from the lock and open it to access its contents.

It’s important to note that using a shim to open a combination lock can damage it, so it’s best only to use this method as a last resort when no other options are available.

Frequently Asked Questions

Q1. How do I set my own combination for a lock?

Answer – Each combination lock will have its own unique instructions for how to set your own combination. Generally speaking, this will involve entering a pre-existing factory code (usually the same code for all locks of that model) before resetting it to the desired code.

Q2. What should I do if I forget my combination? How to figure out a 3-digit combination lock?

Answer – Depending on the type of combination lock you have, there are different methods you can use to reset your code or gain access to the contents inside. Contact your manufacturer’s customer service line if you need assistance with resetting your combination.

Q3. Can I drill open a combination lock if I cannot remember the code?

Answer – Yes, you can drill open a combination lock. However, drilling tools and a certain skill level are needed to succeed. It may also be challenging to do without damaging the process lock. Instead, I suggest using alternative methods, such as cracking the code or using a shim to open the lock if you don’t have access to the combination.


It can be difficult to open a combination lock without the code, but it is possible. By following the steps outlined in this article, you should be able to crack the code and open your combination lock. However, it is important to remember that this process can take some time and require a bit of patience. If you don’t have the right tools or the patience, it’s best to leave it to an expert locksmith. With their help, you can open your lock quickly and easily without any trouble.

For more information and how-to guides on home security, stay tuned!

Leave a Comment

Hey! I am Mark. Though I am not a locksmith by profession, but locks have always fascinated me since my teens. And it all started when I got locked out of my house and I had to pick the lock. Since then it has become my hobby to learn more about different kinds of locks, understand their working and methods to pick them up. In due course of time, I have also become better aware of how installing the right lock goes a long way in ensuring iron clad security. I aim to share my passion (about locks) through this blog. If you are also passionate about picking locks or are just looking to beef up the security, hop on the ride.