Lock It Up: What to Look for in a Bolt Cutter-Proof Lock

by | May 31, 2022

Bolt Cutter-Proof Locks and Padlocks

A door, cabinet, or box is only as strong as its lock. A padlock—any padlock—would certainly seem to provide strong resistance and protection from any would-be thieves looking to gain access to your valuables. But is that actually true? Do padlocks offer the best bang for your buck?

It depends.

Consider the humble bolt cutter. A simple tool that looks similar to a pair of pliers or oversized scissors, bolt cutters are used for a wide variety of legitimate purposes. They can make short work of chains, cables, wires, rebar, nails, wire mesh, and chain link fencing. And, as the name implies, bolts or shackles.

The longer the handles, the more leverage you’re able to exert, which means greater cutting power. For instance, a bolt cutter with 18-inch handles can slice through metals with a diameter of up to 9/32 of an inch. A pair with 48-inch handles? That can work its way clean through rods, chains, and cables up to 7/16 of an inch in diameter.

That brings us back to padlocks. Sure, they look intimidating, but how good are they at resisting 4,000 pounds of force?

Actually, not very good at all. That’s why it’s so important to identify and select a bolt cutter-proof lock.

Padlocks: An Overview

A padlock is a detachable lock that secures via a sliding or hinged shackle. We’ve all seen them on sheds, doors, containers, cabinets, and our locker at school. Some work with a key, while others require a combination.

The global padlock market was worth $13.16 million USD in 2021, with an expected compound annual growth rate of 7.6% for the next 5 years. They’re ubiquitous. And they’re flawed.

Simple Combination Padlocks

A standard padlock comprises a metal body, a keyhole or combination dials, and an exposed metal shackle that looks like an inverted U. The design hasn’t changed much over the years. People have found recognizable padlocks dating back to the Roman Era, ancient China, and the Viking Age.

Cheap padlocks give only the illusion of security. After all, they can be quickly cut or even pried open. They’re all bark and no bite. The body shields the internal workings and locking mechanism but doesn’t protect the exposed shackle. Use brute force or a bolt cutter, and it’s game over.

Advanced Uncuttable Lock Designs

This propensity for failure led to the development of various designs for tamper-proof, uncuttable, and bolt cutter-proof locks. Modern styles include:

  • Brass padlocks – cheaper, rust-proof
  • High-security padlocks – contain hardened steel, shrouded shackle, pick-resistant key cylinder, and/or reinforced locking mechanism
  • Laminated steel – multiple pieces of steel stacked one upon another
  • Discus padlocks
  • Anvil and shutter locks
  • Combination padlocks
  • Shackleless padlocks

Some are better than others. For example, brass locks are cheap and weather-resistant but don’t offer the same protection as hardened steel. Shackles that are 10mm or less in diameter aren’t thick enough. The longer the shackle clearance, the easier it is to cut. Thick and short is the sweet spot.

Design, material, shackle diameter, and shackle clearance all impact a padlock’s durability.

Padlock Diagram

Why Your Property Needs A Cut-Proof Lock

For securing your property, any padlock is better than no padlock, in the same way that any security system is better than no security system. (In fact, you’re 300% more likely to be robbed if you don’t have a security system.) Make your property an undesirable target, even if only superficially. If it looks like a would-be thief must waste valuable time gaining access, they’ll move on to an easier target.

It takes only seconds for a burglar to cut through a shackle. But that’s time they may not be willing to spend. The longer it takes, the greater the risk of getting caught, and burglary is a game of mitigated risk. A fake padlock or dummy security camera is sometimes enough. Of course, a secure padlock and robust security system are even better since they protect you should anyone put them to the test.

A traditional padlock will slow a thief down, but won’t stop them completely. To prevent a crime, you need a high-security bolt cutter-proof lock. Next, let’s look at your options.

Discus Padlocks

Designed by German security company Abus, a discus padlock is extremely reliable for storage lockers, trailers, sheds, shipping containers, and more. The lock exposes only a small section of the shackle at the very top, and the opening below it is typically too small for bolt cutters to go through. The body is either stainless or hardened steel, making it very strong and resistant to corrosion from exposure to the elements.

Discus Padlock

It’s a fantastic choice for anyone looking to secure an outdoor building or container. With only the smallest section of shackle to work with, it’s extremely difficult to latch on and exert enough force to cut it. Some discus padlocks can withstand 8,000 pounds of force, which is double what a standard bolt cutter can deliver.  

Shackleless Padlocks

Going a step further, we have so-called shackleless padlocks. Contrary to the name, these actually do have a shackle, but the steel body completely encases it. No part of it is exposed, making it impossible to tamper with or cut the shackle.

Shackleless Padlock

Shackleless padlocks are generally combined with a specific security “hasp,” or latch. The hasp fits over the staple, which is then secured with a lock. 

Double-Locking Padlocks

Most padlocks only lock on one side, while the other rotates so you can swing the shackle out of the way when unlocked. That’s obviously convenient, but it’s also a flaw. Cut through just one side of the shackle, and you can twist it and remove the lock itself.

A double-locking padlock locks the shackle on both sides. Someone would have to cut through it twice to remove the lock. That takes more time, and more time means greater risk. So, while a double-locking padlock is still technically cuttable, it could give thieves pause.

Alarm Padlocks

Some modern padlocks come with an alarm that is triggered when the lock is jostled or moved. True, the lock itself may or may not be any stronger than any other, but the 120db siren is definitely an extra deterrent.

Closed Shackle Padlocks

A closed shackle padlock is basically a standard padlock with a fortified body that extends up the sides to cover most of the shackle. The shackles are typically thicker than average and made from hardened steel or even boron steel, which is 80% stronger.

Closed Shackle Padlock

This is a bolt cutter-proof lock by design. By further shielding the shackle on both sides, it is extremely difficult for someone to cut through with either a bolt cutter—not enough room to grip and exert force—or an angle grinder—not enough exposed parts.

They operate with either a key or combination, so they may still be subject to picking the lock or cracking the combination.

Get the Best Uncuttable Lock Available to You

Professionals rate locks according to the CEN (Central European Norm) standard:

  • CEN 1 – Low security
  • CEN 2 – Standard security
  • CEN 3 – Medium to high security
  • CEN 4 – High security
  • CEN 5 – Extra high security
  • CEN 6 – Maximum security

Comparing the CEN rating is the easiest way to find a better padlock. Experts consider CEN 4-6 to be insurance-approved and military-grade. However, be aware that the higher the rating, the more expensive the lock. A bolt cutter proof-lock rated CEN 6 can easily cost hundreds of dollars.

Selecting a Bolt Cutter-Proof Lock

With that in mind, let’s look at some of the highest-rated and best-reviewed padlocks available.


Abloy’s Protec2 PL 362 Shrouded Hardened Steel Padlock will set you back $335. It has a CEN 6 rating and a patented top-loading locking cylinder for maximum protection against drilling and cutting. It’s widely considered one of the most secure in the world.


ABUS is a German security company founded in 1924. Since then, the brand has become synonymous with high quality and exceptional strength.

The 37RK/80 KD Granit Extreme Security Steel Rekeyable Keyed Padlock is currently available for $244. It offers a body and shackle constructed from hardened alloy steel, shackle guard protection, and the ABUS-Plus disc cylinder for increased resistance to tampering and picking. ABUS designed the entire Granit line according to Swedish insurance company specifications. Keys can only be copied if you can provide the security certificate.

Henry Squire

The Ss65Cs Stronghold 65Mm Solid Steel Closed Shackle Padlock has a CEN 6 rating, a 13mm shackle diameter, and a hardened steel lock body. It currently sells for $205.75 on Amazon.

Ss65Cs Stronghold 65Mm Solid Steel Closed Shackle Padlock

Only you can determine the value—monetary or otherwise—of the property you want to protect. The higher that value, the better your lock should be. Look at the material, shackle diameter, CEN rating, open vs. closed shackle, and clearance when deciding. And buy the best you can afford.

When an Uncuttable Lock Isn’t Enough

A bolt cutter-proof lock may not be truly uncuttable, given enough time and resources. If a determined thief has the luxury of time to work on the lock—because of an isolated location, for example—they may still crack it. For maximum security, you need an uncuttable lock and eyes on that lock, 24/7/365.

Enter Deep Sentinel.

With its powerful AI and live surveillance guards, Deep Sentinel can identify suspicious behavior, assess the situation, intervene, and notify the police if necessary, all within 30 seconds. In addition, HD video and 2-way audio allow Deep Sentinel personnel to engage with the suspect. A “stop what you’re doing” or “this is private property” often scares them off before damage or crimes occur.

A locked door is better than an open one, but it may not always be enough. A lock that can’t be cut, combined with affordable 24-hour surveillance from trained security personnel, stops thieves dead in their tracks.

Protect what matters most with the best bolt cutter-proof lock you can find—hardened steel, partially or fully shielded shackle, and other enhanced security features to resist tampering—and the industry-leading predict, prevent, and protect security provided by Deep Sentinel.

Need a Solution that Prevents Crime?
Deep Sentinel is the only security technology that delivers the experience of a personal guard on every customer’s home and business. Visit deepsentinel.com/business or call 833-983-6006

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