Quick Links
N-key rollover, referred to as NKRO, is a feature seen in many mechanical keyboards. It allows the user to press multiple keys at once, registering each key press individually. This is particularly useful for gamers who press simultaneous keys.
What Does N-Key Rollover Do?
If your keyboard features NKRO it means each key you press is registered separately. So, if you press three character keys at once in a text document, all characters will display on your screen.
However, there can be limits to the number of keys you can press. This is represented by the "n" in n-key rollover being replaced with a number, e.g. 6-key rollover (6KRO).
Full n-key rollover keyboards allow you to press all of the keys simultaneously; mechanical keyboards leverage this feature more than membrane keyboards.
Common Types of N-Key Rollover
Mechanical keyboards are manufactured to include different types of n-key rollover. This can range from two to unlimited. Here's a breakdown of the most common types:
- 2KRO (2-key rollover)
- 6KRO (6-key rollover)
- 10KRO (10-key rollover)
- 14KRO (14-key rollover)
- NKRO (full n-key rollover)
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 is able to process, an unpressed key could erroneously register. Anti-ghosting prevents this from happening by blocking additional keys from being registered.
For example, on a 3KRO keyboard with anti-ghosting, if more than three keys are pressed simultaneously, it will block a fourth from registering. If the keyboard didn't feature anti-ghosting, you could potentially see five key presses, even though only four were pressed.
Which Keyboards Feature NKRO?
Previously, NKRO was only possible to achieve using a PS/2 connector. Now, PS/2 connectors are far less common, but can still be used with NKRO keyboards if you use an adapter. Modern mechanical keyboards instead have the ability to feature NKRO over USB.
How NKRO Is Useful for Gamers
Mechanical keyboards targeted towards gamers often feature NKRO since some game genres like fighting and FPS require extremely accurate keystrokes and multiple keys to be pressed simultaneously.
Tekken 7, for instance, requires key combinations like 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 wouldn't be possible to unleash this move.
Aside from feeling more immersive, keyboards lacking NKRO is one of the primary reasons that fighting game fans opt for a fight stick.
While most premium mechanical gaming keyboards feature full n-key rollover, it isn't necessarily a selling point that gamers must take up. There are very few games that require more than 6KRO, and unless you are using your keyboard for multiple players, there is no need for anything greater than 10KRO since you only have 10 fingers.
NKRO Can Be Used Outside of Gaming
Although there are a limited number of applications that require you to press multiple keys at once, NKRO does have its place outside of gaming.
One 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 multiple keys down at once, enabling you to create and produce music.
How to Test NKRO on Your Keyboard
Aside from checking the manufacturer's specifications to see what n-key rollover your keyboard has, you can easily test this by using a text application like Microsoft Word.
Start by pressing two keys at the same time, making note of the keys you are pressing, then increase this by one and compare against the key presses registered on your screen.
If you are expecting NKRO from your keyboard but you're not detecting the correct number of key presses, ensure NKRO is activated. Some keyboards require you to turn the NKRO function on using a key combination or via the keyboard's software.
NKRO Can Benefit You
If you're already planning on investing in a mechanical keyboard, chances are you will find one that's suitable for you that also features n-key rollover.
Even the most affordable mechanical keyboards can utilize NKRO; you just have to make the decision as to whether 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 an accurate response.