Keyboard Ghosting vs. NKRO: What’s the Real Difference?

If you have ever purchased a gaming keyboard, you might have noticed some technical terms on the box before even opening it. Often, you will see labels like “Anti-ghosting” or “N-Key Rollover (NKRO)” listed as key features.
But do you actually know what these terms mean and how they affect your typing or gaming experience?

In this guide, we will break down exactly what they do and why they matter.

Close-up of a keyboard with mixed keycap colors; white, gray, and green. Text reads "Keyboard Ghosting vs. NKRO: What's the Real Difference?"

Why Peripheral Performance Matters

This article is specifically for users who rely on high-performance gaming keyboards.
In fast-paced games like Valorant or GTA, players often need to press many keys simultaneously and rapidly.
For these high-level games, only a high-quality gaming keyboard can truly keep up.

However, over time, a keyboard’s performance can degrade, leading to issues like ghosting and rollover errors.
Let’s explore the technical differences between these two concepts.

Close-up of a yellow and gray keyboard with orange letter accents, featuring "High-performance gaming keyboards" in neon text. A website URL is visible.

What is Keyboard Ghosting?

omputer keyboard with a numeric keypad. Keys "W", "E", "R", and "Y" are highlighted in green. The layout is clean, conveying a modern feel.

Many manufacturers use the term “Keyboard Ghosting” incorrectly.
Technically, true ghosting occurs when you are using your keyboard and a key signal appears on your screen that you didn’t actually press.

An Example of Ghosting:

Imagine you are gaming and you press the ‘W’ key.
Suddenly, the ‘Y’ key signal is sent to the computer as well, even though you didn’t touch it.
If this unexpected signal happens repeatedly, it is technically defined as ghosting.

In modern computing, true ghosting is rare.
Manufacturers today build high-quality gaming keyboards that have largely eliminated this hardware flaw.

Understanding Key Rollover (KRO)

When you see “Anti-ghosting” on a box today, the manufacturer usually means Key Rollover.
Key Rollover refers to a keyboard’s ability to correctly identify and register multiple keys pressed at the exact same time.

Rollover is measured using the term “X-Key Rollover,” where ‘X’ represents the total number of keys the hardware can recognize simultaneously.

Alt text: "Virtual keyboard interface showing keys W, A, S, D, F, J, K, V, and N in blue, indicating they are pressed. Statistics above display 'Currently Pressed: 0', 'Max Simultaneous: 6', and 'Total Pressed: 9'."

Types of Key Rollover

Partial Rollover

Found in older or budget-friendly keyboards, this can only recognize a few keys at once.
Often, it only supports specific gaming clusters like WASD.

6-Key Rollover (6KRO)

These keyboards are typically connected via USB.
They can register up to 6 character keys and 4 modifier keys (like Shift or Ctrl) at once.

N-Key Rollover (NKRO)

This is the ultimate version where every single key on the keyboard can work simultaneously.


The ‘N’ stands for an unlimited number, meaning every key signal can be sent and recognized by the computer at the same time.

6-key rollover test results on pctester online"
Full N-key rollover NKRO test showing all keys active"
FeaturePartial Rollover6-Key Rollover (6KRO)N-Key Rollover (NKRO)
Simultaneous Keys

2–3 keys only 25

 

 

Up to 6 keys + 4 modifiers 26

 

 

Unlimited (All keys) 27

 

 

Best Used For

Basic Office Work 28

 

 

Casual Gaming & Typing 29

 

 

Competitive Gaming 30

 

 

Connection Type

Older USB / PS/2 31

 

 

Standard USB 32

 

 

High-end USB / PS/2 333333

 
 

 

Ghosting Risk

High 34

 

 

Very Low 35

 

 

Zero 36

 

 

Key Rollover Test

⌨️ Key Rollover Test

Press multiple keys simultaneously to test your keyboard's NKRO capability

Currently Pressed
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Press any key...
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Note: Some key combinations may be captured by your OS or browser

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USB vs. PS/2: The Hardware Connection

For a long time, tech experts preferred the old purple PS/2 ports over USB.
This was because early USB keyboards were limited to 6KRO.
In contrast, PS/2 keyboards could easily achieve full NKRO, sending all key signals to the computer accurately.

Today, technology has evolved.
Brands like Corsair and Ducky have developed modern USB keyboards that achieve full NKRO performance without needing old ports.

Close-up of a green USB to PS/2 adapter and a purple PS/2 to USB adapter on a reflective silver surface, conveying a tech-related theme.

Do You Really Need NKRO?

Two RGB-lit gaming keyboards are angled against a dark tech-themed background with colored circuit lines. Text at the top asks, "Do You Really Need NKRO?"

While we all want the latest technology, it is important to know what you actually need.

For Gaming and Typing

Most users rarely need to press more than 6 keys at once.
Therefore, a standard 6KRO keyboard is usually more than enough for daily tasks and most gaming needs.

Special Cases

You only truly need NKRO in rare situations, such as using specialized software that turns your keyboard into a piano or other unique technical workloads.

Test Your Keyboard Performance

f you want to check your own keyboard for ghosting or see exactly how many keys it can register at once, we provide a free tool to help. Visit our website at pctester.online to run a live test and ensure your hardware is performing at its best.

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