7+ Types Of House Keys (With Photos)

Jessica Stone
by Jessica Stone

Although a key, if not several of them, serve an important function in our daily lives, they aren’t often given much thought. We put our trust in these small, everyday items to protect ourselves and our loved ones from possible intruders and our possessions against theft. There are many types of keys out there, for different types of locks and each with its own distinct use.

As homeowners, it’s important to be aware of all the different types of house keys available to protect your home. While most are familiar with the standard mechanically cut keys, other options for house keys include double or four-sided keys, dimple keys, abloy keys, and even skeleton keys.

To help you learn more about these essential objects and select the right one for your home, we’ve outlined some of the most common uses for keys, the main parts of a key, and all the various types of house keys you have to choose from.

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Parts of a Key

Although keys may be small and commonly get misplaced, there are very simple devices. The purpose of a key, regardless of the type, is to move the internal components of a lock into the correct positions to unlock the lock. In general, keys are made up of nine main parts, starting at the tip:

  • The tip: The opposite end of the key to the bow, the tip should resemble a ramp, with an inclined angle and a smooth surface. A key’s tip enters into the keyway first and is used to lift the pins. The design of the tip makes it easy to mount the key. It would be virtually impossible to insert a key with a flat or blunt tip, as it cannot enter the first pin. Some locks also use the tip of a key to align the cuts.
  • The warding: Warding essentially refers to the shape or formation of a lock’s keyway, which extends throughout the entire lock. Keys are designed to fit the exact warding shape of the lock. This additional security feature only permits the user to insert a key that has the exact same warding as the lock. The warding also helps hold the key secure when it’s inserted.
  • The biting: This part of the key communicates directly with the internal components of a lock. The biting simply refers to the cuts in the blade, which are basically a combination. When matched with the proper length of the key pins, the biting will open the lock. With pin tumbler locks, once the key is inserted, the biting intermingles with the pins and lifts them to the correct position.
  • The cuts: The cuts make up the biting and are simply the cavities that are cut into the blade. They can be various depths, making up the combination code that matches the lock the key is manufactured for.
  • The blade: The blade refers to the long section of a key that is inserted into the plug of a lock. This functional component contains the biting, warding, cuts, and the tip.
  • The keyway: The keyway of a particular lock determines the overall shape and profile of a key blade. Once inserted, the shape of the key must perfectly match the shape of the lock’s keyway. In other words, they keyway of a key is the appearance of the key that is formed by the wards and the blade.
  • The shoulder: The part of the key that connects the blade to the bow is called the shoulder. It prevents the key from being inserted into the lock further, while also ensuring that the cuts are properly positioned.
  • The bow: The bow, or head, is the handle that is used to turn the key. This component also features important information including the type of key way, codes, and the name of the manufacturer.
  • The code(s): The code or codes are engraved on the bow and may consist of a variety of information pertaining to the key itself. Though, the characters typically indicate the cut depths and the keyway. Some keys stamp the biting code on the bow to help make duplication easier.

Most Common Uses for Keys

Keys can be used in a number of situations, but they serve the same purpose in each: security.


Offices, and commercial and industrial settings are protected with locks that can be opened and closed with a key. In larger buildings, there may a whole series of keys required to access a particular office building.


All cars are operated using some form of key, whether it’s a key that you manually insert or a push-to-start “key.” The purpose of a car key is not only to secure the vehicle and keep it protected from intruders, but also to start the ignition and drive the car.


Keys are used for opening and closing up padlocks, which may be used to protect a wide variety of objects or environments. If you frequent the gym, you may have a padlock to keep your belongings safe inside of a locker while you work out. Or, if you may have a gate on your property you may use a padlock to keep it secure. You can also find much smaller padlocks in use on personal journals and diaries.

The drawback to padlocks is the fact that they are pretty easily compromised. They don’t require much effort to pick, and the padlock keys are simple to duplicated. If someone really wants to get past a padlock, all they have to do is use an angle grinder or a bolt cutter to remove the lock completely and bypass even needing a key.


Safes are impenetrable boxes that typically store items of importance or monetary value. They may be secured using pre-programmed codes or keys. You’ll often find safes inside the closets of hotel rooms, in the back office of restaurants and bars, or even tucked away in a hidden location in your own home. Of course, there are also much more sophisticated safes found in banks.


Last but certainly not least, the most common use for keys is to secure a home. If you live in a house, condo, or even an apartment, odds are you have a key or two. In fact, we rely on our keys to keep us, our loved ones, and our stuff safe. Keys lock up our properties, protecting them against potential thieves or intruders.

When it comes to house keys, it’s likely that you’ll have an entire set: keys for the front door, back door, garage, windows, gate, and may keys to secure a barn, shed, or outbuilding. Since homes are considered by most to be their safe space, it’s worth investing in keys that provide maximum security, giving you proper protection and the utmost peace of mind.

Types of House Keys

Although there is likely only one type of house key that we are most familiar with, there are a number of other types of keys that can be used for the home. These include:

1. Mechanical Cut Key

Mechanical cut keys are typically seen on older car models, as well as doors on homes and commercials spaces. They are only cut on one end, with a design of ridges that links to the corresponding lock. These keys get their name because they are manufactured with a mechanical cutting machine or die-cast.

The major drawback to mechanical cut keys is that they are the easiest type to replicate and, as such, do not provide much security. They have a very simple design, which makes it easy to make duplicates at a hardware store or at a self-service key cutter. In addition to their ease of replication, these keys are very affordable to copy.

That said, if you choose a mechanically cut key for your home, be careful of who you trust with it. Someone could have access to your home by having a duplicate made in just a couple minutes for less than ten bucks. If safety is a priority for you, it’s highly advised that you upgrade any mechanically cut keys to something more secure.

2. Double or Four Sided Key

This type of key is the most common type used on homes. They can be distinguished by the two or four sets of teeth on different sides of the key blade. For optimal security, choose the four sided option. These are the most challenging to duplicate and, therefore, are an improbable target for burglars.

Having multiple lines of teeth means that the lock that the key corresponds to is more complicated and more challenging to pick. If you’re looking to upgrade your mechanically cut house key to something more secure on a budget, double and four sided keys are the way to go. You will drastically improve the security and safety of your home with very little money and time.

In addition to being safer, these types of keys are more durable than conventional single-sided keys. This makes them much less susceptible to breaking in half if they get stuck in your lock.

3. Dimple Key

As the name suggests, these keys feature a number of dimples in various sizes along the blade. These dimples correspond to the protruding pins inside of the matching lock. The way that dimple key works is that once inserted into the lock, the dimples must line up properly with the pins and then the lock is released.

Dimple keys are exactly the same on either side, meaning the key will function regardless of the way that you choose to insert it into the lock. This helps make opening doors easier and faster since you don’t have to waste time figuring out the correct way to hold the key before it can be inserted. These keys are most often used for home security, as they provide an extra level of protection against potential intruders.

4. Abloy Key

Abloy keys are manufactured to unlock disc tumbler locks. Once inserted, the key rotates the internal discs of the lock and when it is correctly aligned the lock with release. In some parts of the world, abloy keys are virtually unknown. Though, there are other places where they are wildly popular. For example, nearly every home in Finland is outfitted with abloy keys as a standard practice.

The major advantage to these keys is that they cannot be picked. This has to do with the fact that the locks are not spring loaded like most other types of locks. For this reason, abloy keys are an excellent choice for providing maximum security to your home. If your goal is to update your home’s security system, consider placing this house key at the top of your list.

5. Primary Key

As the name indicates, a primary key is a type of key that functions as the main key in a building. It has the ability to open every single door. Although there are other keys that match the particular locks, a primary key can unlock all of them as well.

You’ll commonly see these types of keys in office buildings, where each employee might have their own key to their own ice and the primary key can be held by a manager to access all the rooms in case of an emergency. However, primary keys are also often used in apartment buildings for the same reason.

As a tenant, you will have your own key for your unit but your landlord or building manager will have a primary key. Since these keys can unlock every single lock in building, it’s important that it is given to a responsible individual and kept in a safe place.

6. Skeleton Key

Often confused with primary keys, skeleton keys are also referred to as “passkeys.” The confusion between a skeleton key and a primary key stems from the fact that skeleton keys are a form of primary key since they have the ability to open several locks. However, these keys are only used in combination with warded locks.

Skeleton keys feature a serrated, protruding component near the tip of the blade, which has often been sanded down so that it can open a number of locks. For the most part, warded locks aren’t really in use anymore as they are easy to pick and aren’t a great form of security. This has led to the decline of skeleton locks.

Though, you’ll often find that some older homes still have their original warded locks. In either case, it’s highly advised that, if you have a skeleton lock in your home, you should add additional locks to enhance your home’s security. Locks that are opened with skeleton keys feature a spring or lever as their sole internal component, which makes them incredibly easy to pick by hand.

7. Magnetic Key

As the name suggests, a magnetic key contains magnets that, depending on the size the way that they are oriented, will cause the tumblers in a lock to line up correctly and release. These keys use passive systems, with no electronics required. You’ll find magnetic keys in use on a wide range of locks, such as lever locks, deadbolts, and cylinder locks.

Since the grouping of magnets must be so specific in order to operate a lock, magnetic keys are considered incredibly secure. You cannot pick a lock that uses a magnetic key, as physical force would be needed to move the tumblers into the proper orientation. They are also challenging to duplicate, which adds to their level of security.

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Other Types of Door Keys

Although the aforementioned keys are the most common types that you’ll see used in residential settings, they aren’t the only door keys out there. Other types of door keys include:

Key Cards

Keycard keys, or simply ‘key cards,’ appear similar to a credit card, as they are made of the same material and are about the same size and shape. These keys are most commonly used in hotels, which is likely where you first came across them. Though, they are also often seen in large office buildings.

Key cards are very convenient, as they can be easily stored in your wallet alongside your credit cards. They also offer excellent security and since the locks operate electrically, they are impossible to pick.

Cruciform Keys

Also referred to as a ‘cross key,’ cruciform keys only open x-shaped locks. They are typically used in industrial settings, or other situations where a more reliable key is required. These keys are strong, efficient, hardwearing, but also compact. Cruciform keys feature four sides that are all flattened, with teeth in various patterns on each edge.

Paracentric Keys

Paracentric keys can be identified by their twisted shape and tiny, fine teeth at the tip. It’s unlikely that you’ll come across this type of key in your everyday life. In fact, they are usually only seen in prison, as it was once widely understood that these locks cannot be picked. However, nowadays, people have found ways to pick these types of locks and gain access without the need for a paracentric key.

Jessica Stone
Jessica Stone

Jessica considers herself a home improvement and design enthusiast. She grew up surrounded by constant home improvement projects and owes most of what she knows to helping her dad renovate her childhood home. Being a Los Angeles resident, Jessica spends a lot of her time looking for her next DIY project and sharing her love for home design.

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