MMouseTestHQ

Keyboard Tester & Anti-Ghosting Check

Click the test area first, then press any keys. They light up while held. Try the anti-ghosting test below to verify rollover.

Tip: Click anywhere on this page first so the keyboard receives input. Then press keys freely — including modifier combinations (Shift, Ctrl, Alt).
MAIN
NAVIGATION
NUMPAD
Press any key to begin. Last 6 keys will appear here.

Anti-Ghosting / N-Key Rollover Test

Press the highlighted key combination simultaneously. The keys turn green if all are detected, red if any are dropped (ghosted).

Score: 0 / 0

About This Tester

This page listens to keyboard events globally and visualizes every key you press using event.code, which gives the physical key location regardless of your keyboard layout. That's how we can correctly distinguish left vs. right Shift or Numpad 1 from the number row 1.

What is Key Ghosting?

Most cheap keyboards use a 2KRO (2-key rollover) matrix or worse. This means pressing 3+ keys simultaneously can cause some inputs to be "ghosted" — the keyboard fails to register one or more presses. Modern gaming keyboards offer N-key rollover (NKRO), meaning every keypress is registered independently. The test above lets you verify your keyboard's actual behavior.

How the Anti-Ghosting Test Works

  1. Click "Next combo" to load a random combination of keys.
  2. Press and hold all the highlighted keys at the same time.
  3. If every key lights up green, your keyboard correctly registered all of them.
  4. If any key stays red, your keyboard ghosted that input.

Common Ghosting Patterns

  • WASD + Shift: The most common gaming failure — moving + sprinting simultaneously.
  • WASD + Space: Critical for FPS games — moving and jumping.
  • Modifier conflicts: Some boards fail when you press three modifiers at once (Ctrl+Shift+Alt).

Privacy

Keyboard events are processed entirely in your browser. We never log, transmit, or store what you type.