Keyboard Shortcut and Rollover Tester

What is the Keyboard Shortcut and Rollover Tester?

This tool shows exactly which keys your keyboard is registering at any moment when you hold multiple keys down at once. It’s designed to test two specific things:

1. Anti-ghosting — does your keyboard correctly register key combinations it should, or does pressing certain keys together cause others to disappear?
2. N-Key Rollover (NKRO) — what’s the maximum number of simultaneous key presses your keyboard can handle before it starts dropping inputs?

This matters most for gamers who hold down complex combinations (moving + jumping + crouching + reloading), but it’s also relevant for power users who rely on multi-modifier shortcuts.

How to Test Anti-Ghosting and NKRO

1. Click the page to focus the test area.
2. Hold down several keys at once — start with A, S, D, and F simultaneously.
3. Check what appears — do all four keys show up on screen?
4. Keep adding keys — hold those down and add Space, Shift, or Q.
5. Find the limit — if a key fails to appear while you’re holding it, you’ve hit your keyboard’s rollover boundary or a ghosting combination.
6. Check the counter — the “Max Keys Registered” number shows the highest simultaneous count you’ve achieved during the test.

Use Cases

Gaming keyboards — verify that your keyboard lives up to its “full NKRO” claim before relying on it in competitive play where split-second multi-key inputs matter.

Finding ghosting combinations — some keyboards ghost only on specific key combinations. This tool lets you find the exact combos your keyboard struggles with.

Budget keyboard evaluation — before buying a new keyboard, test whether your current one can handle the combinations your workflow or gaming style requires.

Macro and shortcut verification — confirm that complex shortcuts like Ctrl+Shift+Alt+T are registering all four keys simultaneously as expected.

Why Use This Tool

This is a browser-based test that requires no installation and stores no data. It gives you a real-time, precise view of what your keyboard is actually sending to the computer — not what its marketing materials claim.