10 Types of Locks and Where They Work Best

This guide breaks down 10 types of locks, where each one fits best, and how to figure out what makes sense for your home.

1. Deadbolts For Front And Exterior Doors

Deadbolts are the gold standard for exterior door security. Instead of a spring latch, a deadbolt shoots a solid steel bolt deep into the frame—much tougher to force open.

There are three main types to know:

Single cylinder deadbolt: Key slot outside, thumbturn inside. This is what you’ll see on most front doors.
Double cylinder deadbolt: Needs a key on both sides. It’s better for doors with glass nearby, but it can slow you down if you need to get out fast.
Jimmy-proof deadbolt: Mounts on the door’s surface and interlocks with the frame. These are popular on apartment doors and older wood doors.

For real security, pair your deadbolt with a reinforced strike plate and use screws at least 3 inches long. Go for an ANSI Grade 1 or 2 rating if you can. If you want flexibility, a deadlock with a lockable thumbturn gives you options for both safety and security.

2. Knob Locks For Basic Interior Latching

Knob locks are probably the most familiar to most folks. The lock mechanism is inside the knob, which makes them easy to use but honestly not great for exterior doors by themselves.

They’re best for:

Interior bedroom and bathroom doors where privacy is the main goal
Closets and low-traffic doors inside the house
Pairing with a deadbolt on exterior doors for convenience

Knob locks aren’t strong enough for exterior doors—they can be twisted or broken off with simple tools. Keep them for interior doors where privacy is all you need. Their simplicity and low cost are the main advantages.

3. Lever Handle Locks For Accessibility And High-Traffic Doors

Lever handle locks use a horizontal handle instead of a knob. You press or turn the lever to retract the latch, which is much easier for anyone with limited hand strength or mobility.

They’re a good pick for:

ADA-compliant spaces or accessible homes
Office doors, break rooms, commercial restrooms
Interior doors that get a lot of use

One thing: levers can be bumped open accidentally, and on exterior doors, they’re a bit easier to force than knobs. For outside, choose a heavy-duty lever and add a deadbolt. Inside, lever locks are just plain convenient.

4. Mortise Locks For Heavy-Duty Residential And Commercial Doors

A mortise lock fits into a deep rectangular pocket cut into the door’s edge. This makes it super sturdy since the whole lock body sits inside the door.

Most mortise locks combine a latch and a deadbolt in one, usually with a lever or knob. You’ll see them on:

Solid wood or metal doors in older homes
Commercial entry doors and hotel rooms
High-end residential front doors where you want durability

Installing one isn’t a weekend DIY project—it requires a deep cut in the door. Mortise locks are best for thick, solid-core doors. If your door can handle it, a mortise lock is about as tough as they come.

5. Cylindrical Locks For Everyday Keyed Entry

Cylindrical locks—sometimes called bored locks—are the standard keyed entry locks in most US homes. They install through a round hole in the face of the door and a smaller one on the edge.

These are practical for:

Front and back doors in most homes
Rentals, where rekeying is a big deal
Pretty much any door where you want a regular keyed lock and don’t need a mortise

They’re easy to install, easy to rekey, and come in a range of security grades. Not as heavy-duty as mortise locks, but they get the job done for everyday use.

6. Padlocks For Gates, Sheds, And Portable Security

Padlocks are portable—no need to build them into a door. You loop them through a hasp, chain, or latch to secure whatever needs locking.

Common uses:

Backyard gates and fence latches
Sheds, storage units, garages
Lockers, trailers, toolboxes

Keyed padlocks open with a key, while rekeyable padlocks can have their key changed. Combination padlocks skip the key and use a code—handy if multiple people need access.

For outdoor use, look for hardened steel shackles and weather-resistant bodies. A shrouded shackle helps protect against bolt cutters. Padlocks are flexible and work where a built-in lock just isn’t an option.

7. Cam Locks For Cabinets, Mailboxes, And Small Compartments

A cam lock is a small, simple lock where the key turns a flat metal tab (the cam) to block or release the latch. They’re cheap, easy to install, and pretty lightweight.

Best for:

File cabinets, office furniture
Mailboxes and postal cluster boxes
Vending machines, display cases, and electrical panels

Cam locks aren’t built for high-security jobs. They’re there to keep honest people honest and restrict casual access. For cabinets with sensitive stuff or dangerous meds, a cam lock adds a basic layer of control without much hassle.

8. Rim And Surface-Mounted Locks For Older Doors And Apartments

Rim and surface-mounted locks attach to the inside face of a door, not inside a hole or pocket. They’re a practical choice for older doors or apartments where you can’t (or don’t want to) do major modifications.

You’ll see setups like:

Rim cylinder locks with a rim latch or deadbolt
Jimmy-proof deadbolts that surface-mount and interlock with the frame
Night latches as secondary security on apartment doors

These are common in older city apartments with thin or delicate doors. Installation is pretty simple and, since they’re easy to remove, they’re great for rentals. For best results, use a good rim cylinder and a solid strike plate.

9. Electronic Locks For Keypads, Codes, And Managed Entry

Electronic locks swap the usual key cylinder for a keypad, card reader, or fob. You punch in a code or swipe a credential to unlock—and most still have a backup key just in case.

They’re useful for:

Rentals and vacation homes where you want to change codes between guests
Garages or back doors where keys are annoying
Small businesses or offices that want some access control but not a big system

Electronic locks are reliable and cut down on lost keys. Most run on AA or AAA batteries, which need swapping every 6–12 months. You can also tie them into a bigger access control system if you need more features.

10. Smart Locks For Connected Keyless Entry

Smart locks are electronic locks with Wi-Fi, Bluetooth, or Z-Wave built in. You can control them from your phone, set temporary codes, and check who came and went—pretty slick.

Why bother?

Lock and unlock remotely from your phone
Give out temporary codes for guests, dog walkers, deliveries
Connect with Alexa, Google Home, or Apple HomeKit
See activity logs for who entered and when

Smart locks are perfect for tech-friendly homes or anyone managing access for several people. Most replace only the inside part of an existing deadbolt, so the outside hardware stays the same. Just keep in mind, they rely on batteries and your Wi-Fi or hub needs to reach the door.