Will These Keyboard Switches Work With Hotswap Sockets? A Comprehensive Guide

Over the course of the last decade, no technology has been more impactful within the mechanical keyboard hobby than that of the hotswap socket. Often underappreciated and constantly overlooked, these accessories have revolutionized the accessibility of the hobby and made the premise of building, customizing, and owning a mechanical keyboard a reality to countless thousands of people who simply wouldn't have engaged with the hobby at all otherwise.

In fact, I think that the proliferation of hotswap sockets is one of the underlying factors that massively contributed to the explosion of the hobby over the course of the COVID-19 pandemic. But, for all the benefits of increased accessibility that hotswap sockets have granted, I can also see that they've substantially increased confusion among beginners in parallel.

Without a lot of documentation on how hotswap sockets interface with switches, and an equally confusing and ever growing tangle of switch options out there, a lot of people don't readily understand what switches will and won't work with hot swap sockets. While testing switches out for yourself and on your specific board you're wanting to build will always be the most certain way to tell if a switch will work with it, there's also some loose tips that you can use to try and prevent you from having to try every single switch that catches your fancy. Here's a couple of thoughts that you should have when you're trying to figure out if switches will work with your hotswap keyboard or vice versa.

While this may seem like an obvious point to mention for those of you who know a thing or two about switches, you'd be surprised at just how many people freshly into the hobby looking to buy their first keyboards don't already know this! The shape of stems, generally speaking, does not have anything to do with how a switch will or will not fit into a hotswap socket and only matters for your keycaps.

In fact, just because switches look different do not necessarily mean that they won't work in a hotswap keyboard – the only way to tell for sure is looking at the metal pins on the bottom. In general, if a switch is roughly about 1/2 inch in length (~14 mm) on all sides and has a plus shaped cross for where the keycaps go, it's very likely to be compatible with hotswap keyboards if it is not a Hall Effect or Magnetic switch. (For the record this is true for about 95% of all modern mechanical keyboard switches and every single one that Kinetic Labs here sells on their website.)

It doesn't matter if the stems have either full or partial walls that wrap around this plus sign either as these are only aesthetic-based features known as "dustproof walls" that some brands like Kailh and TTC like to add to help their switches stand out. If a switch does not fit that loose criteria that I outlined above, and is instead super short, has some weird keycap compatibility, or is listed as being magnetic, optical, or not MX compatible, then you'll have to resort to turning the switch over to check out it's metal PCB pins.

At the most simplistic of levels, hotswap sockets are just small pieces of metal wiring and plastic that attach to the back of a keyboard PCB and complete the circuit from one switch pin hole to the other. In a normal, solder-only keyboard, you would normally push switch pins into these holes and then use a hot soldering iron to connect them PCB and complete this circuit. However, with hotswap sockets you can just plug and play the switches into the PCB rather than having to solder them in. Thus, in order for switches to work with hotswap sockets, they must have pins that are spaced apart the same as hotswap sockets.

The exceedingly vast majority of hotswap sockets that exist out there for keyboards are listed on sales pages as being "MX compatible" and thus fit switches that have pins that are spaced apart like those of the original Cherry MX switches and all of those that mimic their overall design. As stated above, switches that generally look like Cherry MX switches in shape and size also have pins that fit exactly the same as Cherry switches, though it's often better to be safe than sorry.

In order to figure out for certain if your switch is compatible with MX hotswap sockets, turn it over and either compare it to another MX style switch or look at a chart like the one in the figure below. All the way on the left hand side of this chart, you'll see that normal MX style switches have pins that stick out of the bottom housing and are spaced rather far apart and in a slightly vertically staggered position.

As you move along the rest of the switches in the chart, you'll see that there is a whole array of different orientations in pins that exist among other switches, and especially those that are 'low profile'. Since the metal PCB pins of these low profile switches do not match the layout and spacing of those that are called "MX" switches, they would not be usable in the majority of hotswap sockets. (Although sometimes you can rarely find hotswap sockets that are only compatible with those types of switches!)

Hall Effect/Magnetic switches, by virtue of them not using the same type of switch technology as conventional MX switches, don't require you to have either soldering or hotswap sockets to use them in their proper builds. However, this does not mean that all magnetic switches necessarily work the same with all magnetic switch PCBs. Despite what quite a few vendors will claim, there are cross-brand and cross-switch incompatibilities that do show up when swapping these kinds of switches across boards.

This can arise from several features such as differences in the magnet orientation or the strength of the magnets in the switches. Since all magnets used in switches have a polarity, all HE switches can be grouped into those that either have their north magnetic pole facing up or north magnetic pole facing down towards the PCB. Sometimes, plugging 'north pole up' switches into 'north pole down' PCBs can cause weird actuation issues.

As well, not all magnets are created equally and some can be much stronger than others. HE PCBs from one brand are often tuned specifically to the strengths of magnets in the switches used in those boards, and thus swapping to switches from another brand can cause issues where the PCBs are either struggling to detect a magnetic signal from the switch or are getting overloaded with too much magnetic force.

Unfortunately, unlike the loose guidelines I can give for looking at switches and their pins in normal MX style switch designs, there's really no good way to tell the magnet orientation and strength of switches and PCBs apart when it comes to Hall Effect switches. You'll simply have to consult with manufacturers of the boards and/or switches to see if they've made a cross-brand or multi-switch compatibility chart!

While this is far from an exhaustive or complete guide to help you choose which hotswap switches go with what boards, it is still more of a notice than I've really seen anywhere else. Even just knowing these quick checks to figure out if certain switches will work in hotswap boards or not can more than just help you make informed purchasing decisions – it teaches you quite a bit about one of the most important parts of a mechanical keyboard. In the event you want to learn even more about the complex (and quite interesting) world of keyboard switches, consider checking out some of my other articles here on Kinetic Labs such as The Four Common Types of MX Switch Mechanisms or Linear Switches Aren't All The Same!