What Is the Most Secure Type of Door Lock?

Start with the deadbolt

A deadbolt is a solid metal bolt that slides deep into the door frame. Unlike the spring latch in a knob or lever, it does not rely on a slanted edge that can be pushed back with a thin tool. That is why a deadbolt resists force better than any knob lock.

This matches how our best door lock page treats the topic. We ask first whether a deadbolt is included, because it does most of the work of keeping a door shut. Some products on that page are knobs or levers only, and they should not be your only protection on an entry door.

Understand security grades

In the US, the ANSI/BHMA grade is the quickest way to compare strength. Grade 1 is the highest, Grade 2 sits in the middle, and Grade 3 is the lowest of the three. A grade reflects standardized testing of things like strength under force and durability.

Most products on our comparison page list ANSI Grade 3, and we treat that as a baseline for a front door. If you want the most secure type, look for Grade 1 or Grade 2 hardware, since those grades sit above the baseline. A lock with no grade listed, such as the BESTTEN knob lock, gives you nothing to compare on security.

What makes a lock hard to pick

Picking works by manipulating the pins inside the cylinder. A cylinder is harder to pick when it has tighter tolerances, more pins, and special pins that catch and jam a pick. Makers often call these security pins, and a few use extra features such as sidebars or restricted keys.

Pick resistance is only one piece. Criminals more often kick, drill, saw or pry than pick. Look for these features on the spec sheet or listing:

• A hardened steel bolt, ideally with an anti-sawing insert. The Gobrico lever and deadbolt set lists an anti-sawing bolt.
• A cylinder the maker says resists picking and drilling. The Estmoon set lists a high-security cylinder with this claim.
• A solid metal body instead of thin plastic or hollow parts.
• A bolt that extends a full inch into the frame, which is general industry practice for good deadbolts.
• A strike plate that is screwed into the frame with long screws.

Compare the main lock types

Different lock types trade off security, convenience and cost of upkeep. The table below summarizes how they compare in general terms. Keep in mind that the grade and build quality of an individual model matter more than the category.

Published specifications tell you what a maker claims, not how a lock holds up against a determined attacker. Treat them as a starting point.

Keyed, keypad or smart

A keyed deadbolt is simple and has few parts that can fail. Its weak spot is the key itself, which can be copied or lost. If you want one key for several doors, look for a keyed-alike set. The Estmoon set lists 12 keys in a pack of 2, all keyed alike.

Keypad and smart locks remove the key problem. The TEEHO TE001 lists 20 access codes, a one-time code for guests and Grade 3. It also lists anti-peeping code protection, which helps when someone is watching you type. The Veise VE017 is a Grade 3 fingerprint smart lock, and its listing says access data is stored on the lock with AES128 encryption.

Electronic locks run on batteries, so plan for that. The TEEHO lists 4 AA batteries and a low battery warning light. Keep a backup key or an emergency power option if the lock offers one.

The door and frame matter as much as the lock

A strong lock in a weak door is only as safe as the weakest point. Most forced entries are kicks that split the frame near the strike plate, not attacks on the lock itself.

Here is a short checklist to raise the real security of any lock:

• Use a metal strike plate and fasten it with screws long enough to reach the wall stud behind the frame.
• Choose a solid-core or metal door instead of a hollow one.
• Check that the door is not weakened by a bore hole of the wrong size. The TEEHO needs a 2-1/8 in (54mm) hole and does not fit a 38mm hole.
• Measure door thickness and backset before you buy. Many sets on our page fit doors 1.375 to 1.75 in thick with a 2.375 to 2.75 in backset, while the Veise lists up to 2 in thickness.
• Replace the lock cylinders if you move into a home and do not know who has keys.

Safety notes

Installing a lock means drilling into a door. Wear safety glasses to protect your eyes from wood chips and metal shavings, and wear hearing protection if you use a power drill or hole saw for a long time. Unplug or switch off nothing is needed for battery locks, but keep power tools away from wet areas and use a ladder only if the door is unusually tall.

Never lock yourself in with a key-only deadbolt on the inside. In an emergency, everyone in the home should be able to leave quickly. A thumb turn on the inside is the safer choice for most households, and local fire codes may have rules for your building.

How to choose

Match the lock to your risk and your door. For a typical house, pick a high-grade deadbolt with a pick and drill resistant cylinder and reinforce the frame. If you want keyless entry, choose a graded keypad or smart lock and keep spare batteries on hand.

When you are ready to compare specific models, use the best door lock page to check grade, deadbolt, warranty, cycle rating and fit side by side. Where a maker leaves a spec out, we say so, and you should treat the missing information as a reason to look closer.

Frequently asked questions

Is a smart lock more secure than a key lock?

Not automatically. Security depends on the grade, the bolt and the build. Smart locks add convenience and access control, but they also depend on batteries and software.

Can a deadbolt be picked?

Yes, any pin-based cylinder can be picked by a skilled person. Better cylinders make it much harder, and a strong door frame makes forced entry harder too.

Do more cycles mean a safer lock?

No. A cycle rating shows how many lock and unlock operations the mechanism was rated for. It speaks to durability, not to resistance against attack.

Should I use two locks on one door?

A deadbolt together with a knob or lever set is common and fine. The deadbolt provides the main security, and the second lock handles daily latching.