Keyboard Ghosting Test

Test your keyboard for ghosting and key rollover. Press multiple keys simultaneously to see how many registers. Essential for competitive gamers testing N-Key.

Current Keys0

Max Detected0

Escape

F10

F11

F12

Backspace

Tab

[

]

CapsLock

;

Enter

Shift

Control

What is Keyboard Ghosting?

Keyboard Ghosting occurs when you press multiple keys simultaneously, and your computer fails to register some of them. This usually happens on standard "membrane" keyboards where the internal wiring shares connections (a matrix) between keys to save cost. When you press keys that share the same connection line, the keyboard controller can get confused and "ghost" (ignore) the extra key presses.

For gamers, this is a critical issue. Our Keyboard Ghosting Test helps you identify these limits (also known as "Key Rollover" or KRO).

How to Check Key Rollover (N-Key Rollover Test)

1. Press Multiple Keys

Start by holding down common gaming combinations. Try WASD together, or hold both Shift keys.

2. Watch the Visuals

Green keys are registered successfully. The "Current Keys" counter shows exactly how many inputs your browser is receiving.

3. Find Your Limit

Keep adding keys until new ones stop lighting up. The "Max Detected" number is your keyboard's effective rollover limit (e.g., 6KRO).

Frequently Asked Questions

What is N-Key Rollover (NKRO)?

NKRO means the keyboard can register all keys simultaneously, no matter how many you press. High-end mechanical gaming keyboards often feature NKRO. Standard office keyboards often have 6-Key Rollover (6KRO) over USB.

Why do some keys generally fail together?

This is due to the "matrix" layout of the keyboard's circuit board. Keys are arranged in rows and columns. If you press three keys that form a square on the grid (e.g., Q, W, and A), the keyboard might not be able to tell if the fourth key (S) is pressed or not, leading to ghosting.

Can software fix keyboard ghosting?

No. Ghosting is a hardware limitation of how the keyboard's switches are wired. The only solution is to use a keyboard designed with "Anti-Ghosting" features or NKRO support.