What Is Lock Crunching?

This is the technique of choice for most burglars

House front porch with steps and geraniums
Photo: Marje / E+ / Getty Images
House front porch with steps and geraniums
Photo: Marje / E+ / Getty Images
Sophie Yalkezian
Written by Sophie Yalkezian
Contributing Writer
Updated October 10, 2023

Highlights

  • Lock crunching is a technique in which the exterior of a lock is broken open so the internal workings can be easily picked

  • Locksmiths originated it, but it has been adopted by criminals around the world

  • Single-cylinder deadbolt locks are especially vulnerable to lock crunching

  • The best way to prevent lock crunching is to install and maintain secure locks on all your doors

Get quotes from up to 3 pros!
Enter a zip below and get matched to top-rated pros near you.

Our minds can devise a million scary scenarios in which intruders enter our homes or property. Even though it isn’t likely (FBI crime data shows burglaries were at their lowest in a decade by 2020), chances are that the intruder will have used the lock crunching technique. If you’re scratching your head thinking, “What is lock crunching?” you’re not alone. Let’s dive into what lock crunching is and how to prevent it from happening. 

What Is Lock Crunching? 

This is one of the most common forms of forced entry, and it’s been around for decades. What used to be merely a trade secret among locksmiths has been adopted by thieves and criminals worldwide. 

Lock crunching is a technique originated by locksmiths if a classic cylinder lock is difficult to open. It involves a combination of household tools and brute force to crush the lock's exterior and reveal its inner workings, which are then easily picked and opened in minutes or even seconds. 

Cylinder locks are specifically vulnerable to lock crunching, as the metal tube containing the locking mechanism can be accessed in one location. Unfortunately, cylinder locks are one of the most common exterior door locks in the United States. 

How to Prevent Lock Crunching

Girl unlocking door with a smart door lock
Photo: Helin Loik-Tomson / iStock / Getty Images Plus / Getty Images

Generally, the best way to prevent lock crunching is to outfit your doors with secure locks that are less likely to be crunched and keep the locks well-maintained over time. Many types of deadbolts are on the market, and many beyond the single-cylinder deadbolt variety would do a good job of preventing burglaries. 

Consider a rim deadbolt, electronic, or smart lock to avoid the vulnerability of a single-cylinder deadbolt lock on your door. There are also “anti-snap” locks on the market, which are outfitted with an extra-strong cylinder around the lock that is tested to prevent breaking by burglars using a lock crunching technique.

Consider installing a home security system. Research on alarm and security system efficacy has shown that they deter most burglars from breaking in. Another big advantage is that most modern systems are connected to smartphones, so you’ll be alerted when someone approaches your house, let alone tries entering. If you can afford the cost of a home security system, it’s probably well worth your peace of mind. 

What to Do If You Suspect Lock Crunching

Once you understand the lock crunching techniques and their dangers, you’re better prepared to protect yourself. But the truth is, sometimes it’s hard to tell that your lock has been tampered with. Look for scratches, shiny metal edges, and bending or warping of your lock. If you see anything suspicious, take detailed pictures and notes of the evidence before calling your local police station (or 911) and filing a report. 

When it’s time to reach out to a local locksmith to install a new lock, upgrade your security so this doesn’t happen again. A professional locksmith can confirm whether the lock was tampered with and offer new alternatives to better secure your home. Since this trade is very popular, you may want to research to ensure you choose a reputable locksmith by following our guide to hiring a reliable one. 

Frequently Asked Questions

Using a combination of tools (often store-bought plumbing tools) and brute force, a burglar can easily snap the lock on a door. Snapping a lock aims to gain access to the cylinder inside, which holds the locking mechanism. Once the thief snaps the lock, they can pick the cylinder open and walk right in.

Need professional help with your project?
Get quotes from top-rated pros.
Learn more about our contributor
Sophie Yalkezian
Written by Sophie Yalkezian
Contributing Writer
Sophie loves helping people make the most out of their homes. She is always researching ways to save money through DIY projects as she slowly renovates a 110-year-old Hudson Valley home with her husband. Her work can be found on mortgage and home services startups like Better.com and Landis.
Sophie loves helping people make the most out of their homes. She is always researching ways to save money through DIY projects as she slowly renovates a 110-year-old Hudson Valley home with her husband. Her work can be found on mortgage and home services startups like Better.com and Landis.
The homeowners guide to Locksmiths
From average costs to expert advice, get all the answers you need to get your job done.