What are the 7 types of door locks?

[JaylaLee]

The seven primary types of door locks are knob locks, cam locks, deadbolt locks, padlocks, mortise locks, keypad locks, and smart locks. Each serves distinct security and functional purposes, from basic privacy to high-security and smart access control. The right choice depends heavily on the door type (interior/exterior), material, and desired security level.

Knob Locks are the most common interior door lock. The locking mechanism is inside the doorknob itself. They provide basic privacy but offer minimal security against forced entry, as the external knob can be easily broken. They should never be used as the sole lock on an exterior door. Industry standards, like those from ANSI/BHMA, grade their durability, with Grade 3 being typical for residential interiors.

Cam Locks consist of a base and a rotating metal arm (the cam). Common on cabinets, lockers, and file drawers, they are low-cost and easy to install. Security varies by design; simple flat cams are for basic deterrence, while double or offset cams provide more resistance. They are not suitable for securing room or exterior doors.

Deadbolt Locks are the cornerstone of exterior door security. Unlike knob locks, they lock with a solid metal bolt that extends deep into the door frame, making them highly resistant to kick-ins. Single-cylinder deadbolts use a key outside and a thumb turn inside, while double-cylinder versions require a key on both sides—a safety consideration. ANSI/BHMA Grade 1 deadbolts offer the highest residential security, with bolts that withstand over 10,000 pounds of force and extensive cycle testing.

Padlocks are portable, detachable locks used with a hasp or chain. They come in two main mechanisms: keyed (with a variety of keyway complexities) and combination (dial or digital). Body material (e.g., hardened steel, boron alloy) and shackle thickness directly impact cut resistance. Market data shows laminated steel padlocks are standard for general use, while solid body shrouded padlocks are preferred for high-security applications.

Mortise Locks are installed within a pocket (mortise) cut into the door edge, making them exceptionally strong and durable. They integrate a deadbolt and a spring-latched latch bolt into one unit. Common in commercial buildings and high-end residential doors, they offer superior security but require professional installation due to the complex door preparation needed. Their robust construction often meets or exceeds ANSI/BHMA Grade 1 standards.

Keypad Locks provide keyless entry via a numeric code. They eliminate the need for physical keys and allow for easy code changes. Early models were primarily mechanical (push-button), but electronic versions now dominate, offering features like temporary user codes and audit trails. Battery life is a key consideration, with most models providing low-battery warnings. Their security relies on the strength of the accompanying deadbolt mechanism.

Smart Locks represent the evolution of access control, allowing locking/unlocking via smartphone, voice command, or biometrics. They connect to home automation systems and enable remote access and user activity monitoring. Security experts note that while convenient, their cybersecurity (encryption standards like AES-128) is as crucial as their physical durability. Installation varies; some retrofit over existing deadbolts, while others are full replacement units.

A practical comparison for residential exterior doors:

Lock Type	Best For	Primary Security Feature	Key Consideration
Deadbolt	Primary exterior doors	1-inch (or longer) throw bolt	Must be paired with a sturdy strike plate and long screws.
Smart Lock	Convenience & remote access	Integration with home security systems	Dependent on power (batteries) and network security.
Mortise Lock	Heavy-duty exterior/entry doors	Lock body recessed into door for strength	Requires door modification; professional install recommended.
Keypad Lock	Keyless entry for families/rentals	User-code management	Look for models with a built-in deadbolt for security.

For optimal security, a Grade 1 or 2 single-cylinder deadbolt is the industry-recommended standard for home entry doors, often supplemented by a smart or keypad lock for convenience. Always ensure the door frame and strike plate are reinforced to match the lock's strength.

[Cooper]

As a homeowner who recently upgraded my doors, my advice is to start with the deadbolt. It’s non-negotiable for any door leading outside. I learned the hard way that a fancy knob lock means nothing if the bolt is weak. I went with an ANSI Grade 1 deadbolt—the kind with a solid, one-inch throw. The peace of mind is worth every penny. For my back door, I added a keypad deadbolt. No more hiding keys under the mat, and I can let the dog walker in without being home. Just check the batteries twice a year.

[VivianRose]

I manage a small office, so I see locks from a practical, daily-use angle. Our main entrance has a commercial-grade mortise lock. It’s pricey and was a hassle to install, but it handles hundreds of cycles a day without a wobble. For interior offices and storage, we use knob locks. They’re cheap and fine for indicating if a room is occupied. All our filing cabinets have simple cam locks—they won’t stop a determined thief, but they keep casual prying to a minimum. The real lesson? Match the lock to the traffic and the actual value of what’s behind the door. Don’t put a $20 lock on a door protecting $20,000 of equipment.

[IsaacMarie]

Thinking about locks? Break it down: what are you trying to do?

• Keep a shed shut? A decent padlock.
• Secure a bedroom for privacy? A knob lock is fine.
• Protect your front door? That’s deadbolt territory. Forget about knob locks for outside. The cylinder is the heart of a keyed lock—more pins and a restricted keyway make it harder to pick. Smart locks are cool tech, but remember they’re just a different way to throw the deadbolt. If the underlying bolt is junk, the smart features are pointless. Start with a strong physical lock, then add convenience features on top.

[McKaden]

My perspective comes from renting out a property. Tenant turnover meant constant rekeying until I installed keypad locks. Now, I set a new code for each tenant. It’s cheaper than calling a locksmith every time. I chose a model with a mechanical key override too, just in case the electronics fail. For the interior doors, basic knob locks are sufficient. I did have to reinforce the front door frame before installing a proper deadbolt; the old strike plate was just screwed into the trim. Landlords should view good locks as preventative maintenance—they reduce liability and make the property more attractive. A smart lock with temporary guest codes is a great premium feature for vacation rentals, allowing seamless check-in without key exchanges.