Test Your Keyboard: Ghosting & NKRO Visualizer ⌨️

Verify N-Key Rollover (NKRO) and identify input drops in real-time. This tool helps gamers and hardware enthusiasts ensure every keystroke registers, even during high-intensity play.

💡 What You Can Do

Stop losing matches to hardware limitations. Use this visualizer to verify your keyboard's performance instantly—no software required.

• Verify Gaming Combos: Press complex combinations like WASD + Shift + Space to ensure every input captures simultaneously.
• Identify Ghosting: Detect if your hardware fails to register specific keys when others are held down.
• Audit Hardware Layouts: Toggle between ANSI (US) and JIS (JP) layouts to confirm correct key mapping and firmware behavior.

📘 Pro Tips

• Watch Inputs in Real-Time: Press any key to see it light up instantly on the virtual board.
• Monitor the NKRO Counter: Use the "Active Keys" counter to see exactly how many inputs register at once. Verify if your "6-key rollover" actually hits its limit.
• Complete Input Challenges: Try pre-set clusters like "WASD" or "Home Row" to test common gaming and typing zones.
• Debug Input Lag: Check the event log for millisecond-precise timestamps of every keydown and keyup event.

🧐 FAQ

Q. Why doesn't my 'Fn' key light up? A. The 'Fn' (Function) key is usually intercepted by the keyboard's internal controller and never sends a signal to the operating system or browser.

Q. Can I test mouse buttons? A. No. This tool is built specifically for KeyboardEvent signals. It does not track mouse clicks.

Q. What is 'Ghosting' exactly? A. Ghosting occurs when a keyboard's internal wiring (the matrix) cannot distinguish between multiple simultaneous presses, causing it to either ignore a key or "ghost" a press that never happened.

📚 The Tech: USB vs. PS/2

In the early days of competitive gaming, the legacy PS/2 port was the gold standard because it supported Full NKRO natively. Modern USB keyboards have since caught up, using complex "report descriptors" to bypass the old 6-key limitation. High-end gaming boards now use proprietary controllers to achieve True NKRO over USB, allowing you to mash every single key simultaneously—though you'll likely run out of fingers first.