Switchblade Savvy: Best Automatic Knives in 2021

Why Trust Us

We want the best gear just like you do. If it’s your first time buying an automatic knife, it can be intimidating — what’s the difference between an auto and an assisted opener? What mechanism should I get? What’s the difference between an auto knife and a switchblade?

It was all new to us at one time, too. We looked into it all and drew from our in-house expertise so you didn’t have to.

Who This is For

After keeping an auto knife in my EDC kit for over a month now, I can say I’m a convert. Anyone who regularly uses a pocket knife can benefit from an auto, as long as they can properly clean it.

I’ll reiterate that — I wouldn’t choose to carry an automatic knife in consistently dirty or abrasive conditions. Most of the time, the action bogs down easily when the knife gets too grimy.

But, if you live in an urban area and you need a blade that deploys reliably (or, under adverse circumstances, intimidatingly), an auto knife is a great choice. 

How We Picked

Unlike most product guides I’ve been tasked with, brand reputation is not really a concern with automatic knives. By and large, you have to be all-in as a knife maker to build a switchblade. In that way, the category is fairly unique.

At that point, product choice became a matter of representing multiple approaches and intended uses.

Whatever you want an auto knife for, there should be an inroad toward that choice in this guide.

How We Tested

I tested automatic knives in an EDC capacity — could this blade be carried comfortably, and used reliably in my everyday routine? Feel and utility were my guiding principles. I didn’t want a specialty tool that didn’t make sense in multiple contexts, or an outlier. I wanted workhorses.

I reviewed auto knives based on consistent performance.

Features to Look for in Automatic Knives

Blade Sizes — Consider how long a blade you like, and need, first. Secondarily, blade length can determine an automatic knife’s legality.

If you’re in California, for instance, you’ll need an auto knife with a blade shorter than 2 inches.

Check the American Knife and Tool Institute’s handy reference map here.

Blade Quality — Ah, blade quality in knives. In a perfect world, there would be knife steel that perfectly balanced the qualities of hardness, edge retention, corrosion resistance, ease of sharpening, and every other factor that affects a knife blade’s utility. And that alloy would work equally perfectly under every imaginable scenario.

But this is reality, and every type of steel used for knives is a compromise. They’re all good in some categories and bad in others. I’ll cover the main points of the steel used for each knife in that knife’s specific section.

Material — Knives in this guide include a wide array of materials and alloys commonly used in knives. Each one has its own unique advantages and drawbacks. The main thing to remember is to relate each feature to your own utility; we make it easy by explaining each knife’s specs and features thoroughly.

Edges — The plain edge or serrated? The main advantage of a serrated blade is that it still works when it’s dull.

The blade won’t cut? No problem: just saw your way through. But serrations effectively make the cutting edge shorter; a plain edge blade is a choice for slicing duty.

Keep in mind that for cheap automatic knives, serrated edges may be better — cheaper steel generally dulls easier. And because it’s cheap, you’ll be more prone to abuse it. 

Safety features — Some automatic pocketknives have lock switches or other safety features to prevent accidental opening. An auto knife’s button can be slightly recessed for safety, or the knife can have a separate lock switch.

Strength — For strong auto knife handles, look for aluminum or some other alloy. That’s my recommendation because otherwise, the percussion of the blade’s action can put stress on the handle. If the handle is fiberglass or G10, it won’t last as long as metal.

When it comes to blade strength, 1095 Cro-Van steel is a standby. CPM-3V is quite a bit rarer and usually used for fixed blades, but it’s considered one of the strongest available knife steels.

Longevity — It’s possible to think of knife longevity as a function of a specific knife’s factors and features. True, any cheaply made knife will probably succumb to the sands of time before a high-end blade. That’s because cheaper steels and materials generally degrade faster than more sought-after materials.

However, I’d also argue that any knife will last longer if you love it. If you like the tool, you’ll take better care of it, and thus extend its lifespan.

So, in the hierarchy of your decision process, prioritize your instincts. Based on what you see, do you like the knife? If so, then you should probably buy it.

Types of Automatic Knives

Mechanisms — The four main release mechanisms for auto knives are push buttons, lever locks, and hidden releases. Benchmade automatic knives can incorporate the brand’s patented Axis lock.

Push Button — Straightforward: the user pushes the button, the blade deploys.

Lever Lock —  A traditional automatic knife mechanism, developed in Spain and Italy up to a century ago. Switchblade knives, or more accurately those you’d be inclined to call switchblades, can display lever locks. Instead of a button, the mechanism is triggered by a lever.

Hidden Release — auto knives with hidden releases are rare and interesting birds. The idea is that the release mechanism is unobvious, especially to those unfamiliar with the particular knife. Theoretically, this subterfuge gives the user an advantage.

Axis Lock — Benchmade clearly chose to patent the Axis for highly technical reasons I don’t particularly understand. Essentially, the mechanism is a spring-loaded crossbar that engages the blade on a ramped tang portion. Advantages: ambidextrous operation, wear resistance, and high strength.

Side-Opening — Side-opening automatic knives add a button-operated opening to the classic flipper knife. The blade flips open when the user pushes the button and folds back into the handle to stow.

Side openers can be difficult for some users to handle. Until you figure out just how to hold the knife, it can feel like it’s trying to jump out of your hand when you push the button.

However, they are highly available and generally cheaper than OTF autos. 

Out-the-Front (OTF) — When most people think of switchblade knives, they picture an OTF style auto knife. The blade deploys straight out the front of the handle with a button or switch. Because of the action, OTF knives can be sharp on both sides.

Single Action OTF — The blade of a single action OTF knife must be forced back into the handle manually.

Double Action OTF — The same button or switch both deploys and retracts the blade of a double-action OTF knife.

Q: Are automatic knives legal?

A: It depends on your physical location, and sometimes limitations like blade length, concealed carry, etc. Check out this handy reference from the American Knife and Tool Institute.

Regardless, make sure to check your state’s regulations before choosing a push button knife.

Q: Can civilians own automatic knives?

A: See above. Generally, municipalities make no distinctions between civilian and non-civilian personnel for auto knife laws.

A few states only allow auto knife carry in conjunction with game harvesting.

Interestingly, if you’re in Illinois or Kentucky, you’ll need a concealed carry permit to pack an auto knife.

Q: How do automatic knives work?

A: The difference between an automatic knife and an assisted opener is that an auto knife’s natural position is open. The tension of a spring mechanism holds the blade closed. When the mechanism engages, the blade springs open, and the tension on the springs relaxes.

As you’d imagine, auto knife makers achieve this effect through a litany of different mechanisms.

Q: Is an automatic knife the same as a switchblade?

A: Yes.

By definition, an auto knife’s natural position is open; a spring holds the blade closed. Switchblades satisfy this criterion.

Q: What's the difference between a pocketknife and an automatic knife?

A: All automatic knives are pocketknives but not all pocketknives are automatic knives.

Pocket knives can be conventional flippers, assisted openers, slip joints, frame locks, or generally any variety of folding knives.

It’s only an automatic knife if its natural position is open and a spring lock holds it closed. Some municipalities regulate auto knives specifically; refer “Are automatic knives legal?” above.

Sources:

1. State Laws Regarding Auto-Open Knives - American Knife & Tool Institute