Types of Keys

Car keys, door keys, electronic keys, skeleton keys. There are so many keys for so many different types of locks that it can all get a little overwhelming. While house keys and car keys are relatively common and easy to discern, there are a number of different keys that aren’t common enough to be instantly recognizable.

Here’s a list of some of the many types of keys that exist (that aren’t generic house or car keys).

Transponder Key

Also known as a chip key, a transponder is an electronic key for modern cars that is activated by a radio signal sent from the car when placed in the ignition. These keys are designed to prevent theft, as an incorrect circuit code or if the circuit doesn’t respond. They’re incredibly difficult to duplicate, thus decreasing the chance of someone making a copy and attempting to steal your car. In instances where the wrong key is used, some cars will shut down entirely.


Double/Four-Sided Key

Double-sided and four-sided keys are typically used on home locks. They differ from normal keys in that they have either two or four sets of teeth on them, with the latter resulting in a more durable key. The extra sets of teeth makes the lock more difficult to pick, and are thus a simple way to increase security in your home and deter home invaders.


Paracentric Key

A paracentric key is a key used to open a paracentric lock (obviously). It is recognizable by its small teeth at the end of the key and its contorted blade shape. It is often used in prisons and is used to deter lock picking.


Abloy Key

Well-known for being impossible to pick, an Abloy key is used on disc tumbler locks. These locks use a special key that rotates disc like a tumbler, aligning them into place to unlock. It is springless, and well-known for being impossible to pick. Almost every house in Finland uses an Abloy lock and key system.


Dimple Key

A dimple key is a simple type of key that uses matching cone-shaped dimples on the key that match up with two sets of pins in the lock. The dimples are aligned the same way on each side, meaning the key doesn’t need to be oriented a certain way to work properly.


Skeleton Key

A skeleton key, also known as a passkey, is a simple key with a cylindrical shaft and a single toothed end that is used to open warded locks. Warded locks, however, are no longer in use, and as such the term “skeleton key” has become a catch-all term for keys that can open any lock of a certain type. The well-known “keyhole” icon comes from the design of warded locks.


Tubular Key

Also known as a barrel key, a tubular key is a small key with a cylindrical shaft used to open tubular pin tumbler locks. These keys are typically found in items such as vending machines and bike locks, among others. These keys are often more difficult to duplicate than standard tumbler keys.



If you’ve ever stayed in a hotel you’ve used a keycard. A keycard is a small, flat card that is inserted into a mechanism on the door to unlock it. The mechanism reads the signature, typically found on a magnetic strip on the card, to unlock the door.


Posted on October 9, 2012 at 9:00 AM