How to Open a Master Lock Without a Key: 4 Simple Ways

This expert guide will share some helpful information on how to open a master lock without a key in some easy steps and in less time.

Last Updated on May 2, 2024 by Vincent Zhu

Are you reading this article while you are stuck outside, unable to enter the house because you have forgotten your keys or cannot open the box with a standard master lock?

If so, do not worry. I’m here to help with helpful information.

We will share some helpful information on how to open a master lock without a key. In general, this article will cover four ways that I have selected:

1. Break the padlock with bolt cutters
2. Open the lock with a grinding tool
3. Open the lock with a padlock shim
4. Pick the lock with a paperclip

How to Open a Master Lock Without a Key? Step-by-Step Processes

1. Break the padlock with bolt cutters

This is a quick way to open a standard master lock because the diameter of the shackle is not too large to make it difficult to open.

• Step 1: Choose a suitable pair of bolt cutters. Not all bolt cutters can break a master lock without a key. It would help to choose a pair of bolt cutters about 22 or 24 inches long to create enough leverage for unlocking. The longer the bolt cutters, the more likely you can open locks with large shackle diameters.
• Step 2: Fix the lock with pliers or a vise. This step is optional. However, it will help you a lot in restricting the movement of the lock. Once fixed, all you need to do is put the cutters in so that its two blades fit the shackle.
• Step 3: Apply indirect force on the cutters. Since the cutters are set in a V shape, you need to clamp the sides of the handles so that they come together and form a straight line. That’s only the theory. Therefore, you can stop the process when enough force is applied and the shackle breaks.

2. Open the lock with a grinding tool

It can be anything to grind metal, such as a grinder or any manual sharpener. This method helps you push all the pins inside the lockout.

• Step 1: Check the direction of the lock. That’s the side where the shackles will fall off. You can check it by looking at the keyhole. If either side appears in many rough places, look for the side with signs of serrations on the key.
• Step 2: Smooth the side where the shackle will fall off. Since that will be where the pins exist, you’ll need to grind until you see the pins and they fall out.
• Step 3: Open the padlock. Your lock is no longer entangled with any password. All you need to do is find a flat object that fits into the keyhole. It would help if you twisted slightly at this position, and the shackle would fall off.

3. Open the lock with a padlock shim

Here’s a way to remove a master lock without the key and without physically destroying your padlock. This method is convenient, and I have heard a lot about it. Many people have tried and succeeded, so you can consider trying it.

• Step 1: Prepare tools for the process. You’ll need a can, a pair of scissors, a marker, a ruler, and a pair of pliers. It may seem like a lot, but most of it is small and can easily be found in your car or outside the warehouse.
• Step 2: Prepare the padlock shim.
  • First, you must wash the can and cut off its top and bottom. At this point, cut any straight line from bottom to top to turn the can into an aluminum sheet. Now, you can use pliers to flatten the aluminum plate.
  • Next, rotate the aluminum piece vertically and cut it in half. Then, cut a piece of aluminum into squares with sides about 4-5 cm. Be careful with this step; use a ruler to cut them into square pieces.
  • Finally, divide a square aluminum plate into two parts using a pen. Continue drawing an M shape on one side, but round the corners like the shape of a key instead of a regularly pointed triangle.
  • Here, you need to catch the lower part of the letter M to create a space resembling the shape of two symmetrical keys.
• Step 3: Fold the aluminum piece. For the side without the letter M, fold it in half and stop at the marked dividing line. Next, fold the letter M’s two sides up and the excess back. Adjust it so that the end of the folded section touches the marked line. Use pliers to secure the folded parts in place.
• Step 4: Place the padlock shim in the shackle hole
  • First, from the folded piece of aluminum, put the pen in the center to bend the aluminum piece until it fits the shackle hole.
  • Place the shim into the shackle hole, but do not exert too much force. Distorting the shim’s shape will complicate its working principle. The shackle hole to use is the side where the shackle will fall out.
  • Try to move the shim in a circle from one end to the other. Stay calm if you don’t see movement. It’s looking for the latch inside. Continue moving the shim until you hear a click indicating that you have successfully opened a master padlock without a key.

Some locks require two shims on either side of the shackle hole to open, so please cut them into equal squares instead of one piece.

4. Pick the lock with a paperclip

I have tried using two paper clips, but it isn’t easy and takes a long time for a beginner.

So, I want to show you an easier and more helpful way I learned from a YouTuber with just a paperclip. This is also a way of opening a master lock without a key where you don’t need to break your lock.

• Step 1: Cut one end of the paperclip. Use pliers to cut off one end of the paperclip with no circular crease.
• Step 2: Place the two sticks on either side of the paper clip to fit snugly into the lock. Choose a stapler that is small enough to fit into the keyhole. It cannot put enough pressure on the pins inside if it’s bigger or smaller.
• Step 3: Use a screwdriver to unlock. At this moment, it will act as a lever for the lock. Use a screwdriver with a crossbar instead of a cross, which is small enough to be inserted into the keyhole. Then, you can open the lock with slight movements when the shackle comes out.

Pro-tips: