Nowadays, more and more people are asking what bump keys are.* However, no one could really give them a straight answer.* This is because not a lot of people have the answer!* Those who practice it kept it under wraps, so to speak.* It’s either they want to keep the precious secret to themselves or [...]
Nowadays, more and more people are asking what bump keys are.* However, no one could really give them a straight answer.* This is because not a lot of people have the answer!* Those who practice it kept it under wraps, so to speak.* It’s either they want to keep the precious secret to themselves or they’re concerned that sharing the information can get them in trouble with the law.

Definition of bump keys

An Example of a Bump Key

Simply put, they are keys that were manipulated to work in just about any lock that the blanks are designed for.* Each type of lock has a type of blank that’s used to create duplicates for a specific lock.* Instead of manipulating them to work on a single lock; you’re going to manipulate them so that they’re going to work on all locks of that specific lock type.


Bump keys have a relatively long history.* A similar device was patented from 1926 to 1928.* But it was H.R. Simpson who came up with the design and idea that we know today.* Back then, he already called it a bump key which he also called as a rapping key.* Recognizing its potential, he quickly applied for a US patent back in 1928.

However, it wasn’t until 1970 that it was recognized mainstream by locksmiths.* That was the time when Danish locksmiths revealed a technique on how to use a bump key in order to make the pins of a lock jump so that proper timing can be used in order to turn the plug.

But its most recent history contributed to its popularity or notoriety.* Klaus Noch exposed it as a security risk around early 2000 and together with the German media; they spread the word that it can be a potential headache as far as security is concerned.

The Open Organization Of Lockpickers (TOOOL) also saw the same risk and this is the reason why they drafted a report detailing the issue back in 2005.* TOOOL went on and conducted public presentations to show how bump keys can be used to defeat locks.

Security Expert Marc Tobias

The US followed suit as security expert Marc Tobias also released a couple of reports in 2006 that tackled the security and legal issues that these keys bring.

Bump keys and lock bumping

Lock Bumping

Lock bumping is a method for defeating locks using bump keys instead of the keys that are specifically-designed for them.* Using just about any hand tool, you’re going to give the key a slight bump and let the bump key do the work.* It’s a popular method because it’s very easy and there’s no need for lock picking skills in order to do it.* You just need to know how to do it and you need to have the tools to do it.

Unfortunately, the fact that it’s very easy is also the reason behind its notoriety.* Here are some reasons why homeowners and security experts are concerned:

  • Even the dumbest criminals can make a bump key in 5 - 15 minutes.* They can also master how to bump locks with very minimal practice.
  • 9 out of 10 homes in the US are not protected against lock bumping.
  • Done correctly, there will be no damages to the lock.* Try explaining to your insurance company or to the police that you were broken into when there are no signs of forced entry.
How to make bump keys

As mentioned, it’s very easy to make them.* Here are the things that you need to make one:
  • Blank key for your target lock
  • Triangular file
  • Flat working surface
It won’t even take you an hour to gather the needed equipment.* Making a bump key out of them is also very easy.* Just follow these easy steps:

  • Determine the maximum depth of the grooves of the blank key.* The locksmiths call it 999.
  • Place the blank key on the flat surface.* A strong table works best.
  • Using the triangular file, file down the grooves so all of them are at the maximum depth.* The grooves should now be of equal depth and the tips of the grooves should be of equal height.
Types of lock that they work on

An Inside Look at a Pin Tumbler Lock

Generally speaking, they can work on just about any lock that has pins with just a few exceptions. You just need to make sure that you’re going to craft them from blank keys that are made for the specific lock that you need to open.

Bump-resistant locks

Through the years, lock manufacturers have tried putting security measures to protect their locks against bump keys.* They introduced security pins like mushroom pins.* However, they only made it harder to bump the lock.* They didn’t really make it impossible.

Trap Pins

Locks that are protected with trap pins are considered as bump-free since these trap pins will block the cylinder of the lock when a bump key is used.* There are also locks that have pin stacks that don’t have the same depth as the other pin stacks.* Since they’re shallow, the bump key won’t be able to engage.

Are Bump Keys Illegal?

Are Bump Keys Illegal?

Generally speaking, the mere possession of bump keys is not illegal in itself. You can think of it as lock picks.* In most areas, you’re not going to get arrested just by possessing them.* There must be an intent to commit a criminal act.* However, there are areas wherein you need to be a licensed locksmith in order to possess them.* Suffice to say, you need to check for local laws if you want to make one.* There’s also the issue of buying them.* There are now a lot of sites that sell them and a lot of people are asking if it’s legal to buy them.

The law is very vague about this and it leaves a lot for interpretation.* However, these are the federal statutes that may be used for or against you:
  • Title 18, USC 1704 (Keys or locks stolen or reproduced)
  • Section 83 USC 1716A and 39 USC 3002(a) (Nonmailable locksmithing devices and motor vehicle master keys
  • 39 USC 3002 (Nonmailable motor vehicle master keys)
  • Title 19, USC 1583 (c) (1) (E) (Examination of outbound mail)
    Of course, it goes without saying that using them to break into locks without the owner’s permission is illegal.

    Where can they be bought?

    As mentioned, there are a lot of internet sites that sell them.* You can do a simple search for bump keys or 999 keys and you’ll be presented with a lot of results.* In addition, you can also buy them from locksmiths since they have the tools to make them.* However, majority of locksmiths are apprehensive about selling them.* This is the reason why most people choose to make them.