N-key rollover, called NKRO, is a feature found in many mechanical keyboards. It allows the user to press multiple keys at once, registering each keypress individually. This is especially useful for players who press keys simultaneously.
What does N-Key Rollover do?
If your keyboard features NKRO, this means that each key you press is recorded separately. So if you press three character keys simultaneously in a text document, all the characters will show up on your screen.
However, there may be limits to the number of keys you can press. This is represented by the “n” in the n-key roll being replaced by a number, for example the 6-key roll (6KRO).
Full n-key rollover keyboards allow you to press all keys simultaneously; mechanical keyboards take advantage of this feature more than membrane keyboards.
Common N-Key Bearing Types
Mechanical keyboards are manufactured to include different types of n-key bearing. It can range from two to an unlimited number. Here is a breakdown of the most common types:
- 2KRO (2-key rollover)
- 6KRO (6 key bearing)
- 10KRO (10 key rollover)
- 14KRO (14 key rollover)
- NKRO (full n-key bearing)
Is N-Key Rollover the same as Anti-Ghosting?
It is common for NKRO keyboards to feature anti-ghosting. If you press more keys at once than a keyboard can handle, an unpressed key may be registered by mistake. Anti-ghosting prevents this from happening by blocking the registration of additional keys.
For example, on a 3KRO keyboard with anti-ghosting, if more than three keys are pressed simultaneously, it will prevent a fourth from registering. If the keyboard didn’t feature anti-ghosting, you could potentially see five key presses, even if only four were pressed.
What keyboards have NKRO?
Previously, NKRO was only possible with a PS/2 connector. Now PS/2 connectors are much less common, but can still be used with NKRO keyboards if you use an adapter. Modern mechanical keyboards instead have the option of offering NKRO via USB.
How NKRO is useful for gamers
Mechanical keyboards aimed at gamers often feature NKRO, as certain genres of games like fighting and FPS require extremely precise keystrokes and multiple keys to be pressed simultaneously.
Tekken 7, for example, requires key combinations such as F, D, 2, and 1 to be pressed at the same time to perform an attack. If your keyboard is limited to 2KRO or 3KRO, it would not be possible to trigger this move.
Along with feeling more immersive, NKRO-free keyboards are one of the main reasons fighting game fans opt for a fight stick.
While most high-end mechanical gaming keyboards feature full n-key rollover, that’s not necessarily a selling point for gamers to embrace. There are very few games that require more than 6KRO, and unless you’re using your keyboard for multiple players, there’s no need for more than 10KRO since you only have 10 fingers.
NKRO can be used outside of the game
Although there are a limited number of apps that require you to press multiple keys at once, NKRO has its place outside of gaming.
An example is music creation software. If you don’t have a MIDI keyboard, you can use your PC’s mechanical keyboard as a replacement. This will allow you to hold down multiple keys at once, allowing you to create and produce music.
How to test NKRO on your keyboard
Besides checking the manufacturer’s specs to see your keyboard’s n-key rollover, you can easily test it using a text application like Microsoft Word.
Start by pressing two keys at the same time, noting which keys you press, then increase it by one and compare it to the key presses recorded on your screen.
If you’re expecting NKRO from your keyboard but not detecting the correct number of key presses, make sure NKRO is enabled. Some keyboards require you to enable the NKRO feature using a key combination or through the keyboard software.
NKRO can benefit you
If you’re already considering investing in a mechanical keyboard, chances are you’ll find one that’s right for you that also features n-key rollover.
Even the most affordable mechanical keyboards can use NKRO; you just have to decide if a mechanical keyboard is the right choice. If you’re a typist or gamer, it’s worth spending a little extra on an NKRO keyboard to ensure accurate response.