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How Do I Know If a Switch Will Fit My Keyboard?
You have found new keyboard switches, but before ordering them you naturally want to know whether they will actually fit your keyboard.
How do you check that?
The appearance of a switch alone is not enough to determine compatibility.
You need to look at switch technology, footprint, 3-pin or 5-pin mounting, PCB, plate and hot-swap system, among other things.
Quick explanation
First check which switch type your keyboard uses. If it supports standard MX-style mechanical switches, many Cherry, Gateron, Kailh, TTC, HMX and similar switches will fit. Then check whether the PCB supports 3-pin or 5-pin. Optical, Hall Effect, low-profile and proprietary switches should be treated as separate systems.
1. Start with the type of switch your keyboard uses
The first step is determining which technology your keyboard uses.
The main categories are:
- traditional mechanical switches;
- optical switches;
- Hall Effect switches;
- low-profile switches;
- proprietary switch systems.
Switches from different categories are usually not interchangeable.
2. How do you know if your keyboard uses standard mechanical switches?
Check the product specifications of the keyboard.
Terms that may indicate traditional mechanical switches include:
- MX-style;
- Cherry MX compatible;
- 3-pin mechanical switches;
- 5-pin mechanical switches;
- MX hot-swap.
If the keyboard explicitly mentions optical or Hall Effect, you should not assume normal mechanical switches will fit.
3. What does MX-style mean?
MX-style means the switch largely follows the Cherry MX format.
Many brands produce switches using this basic shape.
Examples include:
- Cherry;
- Gateron;
- Kailh;
- TTC;
- HMX;
- Akko;
- Everglide;
- many other switch manufacturers.
If your keyboard supports standard MX-style mechanical switches, you usually have a very wide selection.
4. Are all MX-style switches automatically compatible?
No.
MX-style is a good first indication, but you still need to look at the bottom of the switch and the PCB.
3-pin and 5-pin mounting in particular can make a difference.
5. Check whether your keyboard supports 3-pin or 5-pin
A standard mechanical MX-style switch can have 3-pin or 5-pin mounting.
A 3-pin switch has:
- 1 central plastic mounting pin;
- 2 metal electrical contact pins.
A 5-pin switch also has two additional plastic stabilizing pins.
6. How do you identify a 5-pin PCB?
If necessary, remove one switch and inspect the PCB.
With a 5-pin footprint, you normally see:
- 1 larger central hole;
- 2 holes for the electrical contacts;
- 2 additional smaller holes for the plastic stabilizing pins.
That gives you a total of five relevant openings for the switch.
7. How do you identify a 3-pin PCB?
A 3-pin footprint is missing the two additional holes for the stabilizing pins.
You normally see:
- 1 central hole;
- 2 holes for the electrical contacts.
8. Does a 3-pin switch fit a 5-pin PCB?
Usually yes.
The two additional stabilizing holes simply remain unused.
This generally makes a 5-pin MX PCB suitable for 3-pin MX switches as well.
9. Does a 5-pin switch fit a 3-pin PCB?
Not without modification.
The two additional plastic stabilizing pins have no holes to go into.
With standard MX-style switches, these two pins can usually be clipped off.
Read our guide: Can You Put 5-Pin Switches in a 3-Pin Keyboard?
10. What exactly is the difference between 3-pin and 5-pin?
The difference is mainly mechanical stability.
A 5-pin switch has two additional plastic support pins.
For a complete explanation, read: What Are 3-Pin and 5-Pin Keyboard Switches?
11. Check whether your keyboard is hot-swappable
Hot-swap means you can remove and replace switches without soldering.
If your keyboard is not hot-swappable, the switches are normally soldered to the PCB.
You can still replace the switches, but you will usually need to:
- desolder the old switches;
- install the new switches;
- solder the new switches again.
12. Does hot-swap mean every switch fits?
No.
Hot-swap only tells you how the switch is installed and replaced.
The socket can still be designed for a specific type of switch.
An optical hot-swap keyboard, for example, does not automatically use the same switches as an MX mechanical hot-swap keyboard.
13. How do you identify an MX mechanical hot-swap keyboard?
Check the product specifications.
Look for terms such as:
- MX mechanical hot-swap;
- 3-pin/5-pin hot-swappable;
- Cherry MX compatible;
- Gateron/Kailh/Cherry compatible.
If several standard MX brands are explicitly mentioned, that is usually a strong indication that it uses a regular MX mechanical socket.
14. What if the manufacturer only says “hot-swappable”?
That is not enough information to guarantee full compatibility.
Check which switches come installed in the keyboard and which switch families the manufacturer supports.
Hot-swappable is not a universal switch standard.
15. Check the switches already installed in the keyboard
An easy way to learn more is to look at the current switches.
Note:
- brand;
- model;
- 3-pin or 5-pin;
- standard-height or low-profile;
- mechanical, optical or Hall Effect.
This makes it much easier to determine which alternatives are suitable.
16. Can you tell which switches fit from the brand?
Not reliably.
The same brand can produce multiple switch systems.
Gateron, for example, makes traditional mechanical switches, low-profile switches and Hall Effect switches.
So look at the specific switch model, not just the brand.
17. How do you know if you have optical switches?
Check the specifications of the keyboard or the current switch.
Optical keyboards use light to detect the keypress.
They therefore use a different detection system from traditional mechanical contact switches.
18. Does a normal MX mechanical switch fit an optical keyboard?
Usually not.
Even when the switch physically resembles an MX switch, the keyboard uses a different detection method.
You need switches specifically compatible with the keyboard's optical system.
19. How do you know if you have Hall Effect switches?
Hall Effect keyboards are often described using terms such as:
- Hall Effect;
- HE;
- magnetic switches;
- adjustable actuation;
- Rapid Trigger.
Keep in mind that adjustable actuation and Rapid Trigger are strong indicators, but you should still check the official specifications.
20. Does every Hall Effect switch fit every HE keyboard?
No.
Hall Effect compatibility can depend on:
- magnet position;
- magnet strength;
- switch height;
- PCB sensor position;
- footprint;
- firmware;
- calibration.
For HE keyboards, preferably use switches known to be supported by the keyboard.
21. Does a Hall Effect switch fit a normal mechanical keyboard?
Normally not.
A traditional mechanical PCB detects the closing of electrical contacts.
A Hall Effect PCB measures the movement of a magnet.
These are two different systems.
22. How do you identify low-profile switches?
Low-profile switches are significantly shorter than standard MX-style switches.
The complete keyboard is usually noticeably thinner as well.
Well-known low-profile switch families often have their own:
- footprints;
- pin layouts;
- stems;
- keycaps.
23. Do normal MX switches fit a low-profile keyboard?
Usually not.
The PCB and plate are designed for the shorter dimensions of the low-profile system.
Standard-height MX switches are usually too large and may also use a different connection.
24. Is the same MX keycap stem enough to determine compatibility?
No.
The top of the switch mainly determines which keycaps fit.
The bottom determines whether the switch works with the PCB and mounting of the keyboard.
A switch can therefore use MX-compatible keycaps without being fully MX mechanical compatible.
25. Should you check the plate?
Yes.
Most standard MX-style switches use similar plate openings, but there can be exceptions.
The plate can affect:
- how securely the switch clips in;
- whether the housing physically fits through the opening;
- whether certain additional clips or shapes have enough room.
26. Can a switch fit the PCB but not the plate?
Yes.
Electrical compatibility does not automatically guarantee that all physical parts of the keyboard provide enough space.
This is less common with normal MX-style switches, but it is possible with unusual switch designs or plates.
27. Does north-facing or south-facing matter?
Usually not for the electrical switch connection.
North-facing and south-facing refer to the orientation of the switch and LED.
It can, however, affect:
- RGB lighting;
- space around certain housings;
- interference with certain keycap profiles.
28. Should you pay attention to SMD compatibility?
If your keyboard has LEDs directly on the PCB, this can be relevant.
SMD-compatible switches generally have enough space or transparency for light from the PCB LED to pass through the switch.
This mainly affects RGB performance and does not always determine basic electrical compatibility.
29. How do you check a switch product page?
At minimum, look for:
- switch type;
- MX-style or another format;
- 3-pin or 5-pin;
- standard-height or low-profile;
- mechanical, optical or Hall Effect;
- SMD support if relevant.
Compare this information with the specifications of your keyboard.
30. How do you check a keyboard product page?
Look for information such as:
- hot-swappable or soldered;
- 3-pin support;
- 5-pin support;
- MX-compatible;
- optical;
- Hall Effect;
- low-profile;
- officially supported switch brands or models.
31. What if the specifications are unclear?
Do not automatically assume compatibility.
You can:
- remove the current switch and inspect the footprint;
- look up the current switch model;
- check the manual;
- consult the manufacturer;
- look at photos of the PCB.
32. What if you only want to test one new switch?
If possible, test one switch before buying a large quantity.
Check whether:
- the switch physically fits;
- the pins do not bend;
- the switch sits securely;
- the key registers;
- the keycap fits correctly.
This can be especially useful when a keyboard's compatibility is poorly documented.
33. Quick compatibility check
| Check | What needs to match? |
|---|---|
| Switch technology | Mechanical / Optical / Hall Effect |
| Format | MX-style / Low-profile / Proprietary |
| Mounting | 3-pin / 5-pin |
| PCB | Correct footprint and detection method |
| Plate | Switch must physically fit |
| Hot-swap | Socket must support switch type |
| Keycaps | Stem must be compatible |
34. Which switches usually fit a normal MX hot-swap keyboard?
If your keyboard uses a regular 3-pin/5-pin MX mechanical hot-swap PCB, you can usually choose from a very large range.
This includes many:
The internal feel of the switch does not change the basic footprint as long as it uses the same MX mechanical standard.
35. Common mistakes
- Only looking at the top of the switch.
- Thinking every hot-swap switch fits every hot-swap keyboard.
- Confusing MX keycap compatibility with full switch compatibility.
- Not checking 3-pin and 5-pin.
- Confusing optical and mechanical switches.
- Treating Hall Effect switches as universal MX switches.
- Confusing low-profile and standard-height switches.
Conclusion
To know whether a switch will fit your keyboard, you need to check more than just the brand or appearance.
Start with the technology: mechanical, optical or Hall Effect.
Then check the format, footprint, 3-pin/5-pin support, PCB, plate and hot-swap socket.
If your keyboard supports standard MX-style mechanical 3-pin/5-pin switches, you usually have a very wide choice of different brands.
But with optical, Hall Effect, low-profile and proprietary keyboards, you need to specifically check which switch family is supported.
Not sure? Never force a switch. Check the specifications first or test one switch.
Also read our guide: Are All Mechanical Keyboard Switches Universal?