What is a Hall effect keyboard, and do you need one?

Take a scroll through some of the best gaming keyboard releases over the last year and you’ll likely come across a technology that’s sprinted to mainstream popularity. Hall effect keyboards are on the up, and everyone from SteelSeries to Corsair is getting in on the action. Originally designed for (you guessed it) military purposes, these super-fast decks come with a heap of benefits, but an equally stacked price tag in some cases.

In short, the best Hall effect keyboards use magnetic switches instead of the traditional metal contacts found in mechanical models. They’re much better for repeat presses, last longer, and can be adjusted with customized actuation points. Exactly how they do that requires the toolbox.

What's the difference between Hall effect and mechanical keyboards?

Cracking open a traditional mechanical switch, you’ll find five main parts. From top to bottom, there’s an upper casing (the plastic cover keeping everything together), a stem (the piece of plastic that runs through the switch and attaches to a keycap), a spring, metal leaf contacts (the folded loop at the back of the switch), and the lower casing (the plastic base). Everything slots together, with the stem feeding through the middle of the spring and being held in place by two small ridges on each side. The most important part of the stem is its two little arms at the back. That’s where the metal contacts come into play. This is, essentially, a loop of metal that folds down and spreads across the width of the switch, with two humps reaching out to join the arms of the stem. A separate contact plate sits between the leaf and the stem.

When assembled, the stem’s arms hold the leaf away from this contact until pushed - at which point the arms move below the humps, allowing the metal to close the circuit with the contact plate. This is the actuation point, the moment at which a key press is registered by a computer. I’m sure there are technical words for both ‘arms’ and ‘humps’, but break a switch apart and you’ll see what I mean.

This is the system the world used for gaming keyboards for years - it’s tactile, satisfying, and relatively foolproof. It’s also pretty rigid. You’ll need to fully hit the set actuation point (the moment the arms drop away from the metal leaf) and then wait for the switch to hit its fixed reset position (the moment the arms return to the leaf) in order to repeat a press. A Hall effect switch can reset pretty much instantaneously.

Instead of all these humps and arms, a Hall effect switch features a magnet placed at the bottom of the upper housing stem. This travels down the switch as it’s pressed, its distance from a sensor in the PCB of a keyboard decreasing the whole time. The keyboard knows this, it’s measuring the magnetic field. That means it knows where the magnet is in relation to the bottom-out (the point where the key is fully pressed down), and it knows the moment it starts to rise again.

This use of a magnet turns our keyboard inputs from fixed to dynamic. Once a computer knows how far you’ve pushed the key down at any one moment, it can react far quicker to smaller movements. It can also be customized to use any distance between the magnet and the sensor in the PCB as an actuation point.

Do you need a Hall effect keyboard?

At this point in time, the only players who strictly need a Hall effect keyboard are those at the top of their competitive league tables. The speed these keyboards bring to the table is impressive, and Rapid Trigger is one of the biggies you’ll hear about the most. From the Endgame Gear KB65HE to the SteelSeries Apex Pro TKL Gen 3, this is the feature most gaming brands shout the loudest about.

Because magnetic switches don’t need to return to a fixed reset position, they can register as ‘reset’ as soon as you lift the pressure even a little bit. This ‘off’ point can move dynamically with your keystroke. Say you’re spamming a particular key, you’ll need to actuate and reset the switch fully every time you want it to register- that’s a much larger movement compared to the minute shifts in pressure a Hall effect switch can detect.

This kind of speed is only going to be noticed by those at the top of their game, where milliseconds count in the fastest of arenas. If you don’t play competitively, you can rest assured that you likely aren’t being held back by a traditional mechanical gaming keyboard.

There are other benefits to Hall effect keyboards, they’re more durable overall with no metal contacts to worry about (though hot-swappable keyboards also clean up that worry), and they can be set up with dual actuation.

This is where I think most players will find the benefit in a Hall effect keyboard right now (it is worth noting some optical keyboards also support this feature, but it’s not quite as widespread). Because your computer knows much more about your keypress, you can tell it to do different things based on how far down the press you are. This is known as dual-actuation - you can set two different inputs to one key, with one being registered at just a tap, for example, and the other registering at a full bottom-out. A word of warning, this takes some getting used to. I’ve tested a number of Hall effect keyboards over the last year, and I’m still in the process of committing my usual keybindings to muscle memory. Once you’ve got it down, it’s pretty hard to go back.

I usually keep my W key set to walk when lightly pressed and run when fully pushed, but have dabbled with different grenade types set to different Q actuation points and different health items tucked away on the Tab key. Some keyboards, like the Glorious GMMK 3 HE, offer up to four different inputs this way - a feature that generally only makes sense for regularly used combos, as it relies on a full keypress action to run through all commands in sequence (push down, bottom out, release, fully reset).

It’s by no means a make or break feature, but it is a key draw of Hall effect keyboards outside of competitive play.

Hall effect keyboards are by no means essential, but they are typically faster, more customizable, and more durable than their mechanical counterparts. If you’re looking to invest in a deck that can introduce some new functionality while still feeling great under the fingertips they’re certainly worth taking a look at.

There are also plenty of Hall effect switches in the best wireless gaming keyboards, though they can cost a lot more - if you’re after a budget-friendly deck, the best membrane gaming keyboards still provide plenty of features. For a full setup renovation, check out the best gaming mouse models available as well.