NKRO Test
Find out how many keys your keyboard can handle at once. Professional N-Key Rollover testing tool with visual keyboard display.
N-Key Rollover Test
What is N-Key Rollover (NKRO)?
N-Key Rollover measures how many keys your keyboard can accurately register when pressed simultaneously. A "6KRO" keyboard can handle 6 keys at once, while "NKRO" means unlimited.
Why Does It Matter?
Many keyboards (especially laptops and membrane keyboards) suffer from "ghosting" — when you press certain key combinations simultaneously, some keys fail to register or phantom keys appear.
This matters for:
- Gaming: FPS games often require holding movement + crouch + fire keys simultaneously
- Music Production: Triggering multiple notes/chords at once
- Fast Typing: Keys overlap during rapid typing
How to Use
- Press any key — it lights up on the virtual keyboard
- Hold multiple keys simultaneously and watch the "MAX NKRO" value
- Try different key combinations — some areas may support more simultaneous keys than others
- Previously tested keys remain marked on the keyboard
Reference Values by Keyboard Type
- Mechanical Keyboard (USB): Usually 6KRO to full NKRO
- Mechanical Keyboard (PS/2): Almost always full NKRO
- Membrane Keyboard: Usually 2-4KRO
- Laptop Built-in Keyboard: Usually 3-6KRO
- Bluetooth Keyboard: Limited to 6KRO by Bluetooth HID protocol