Keyboard Ghosting and Rollover Test
Hold down as many keys as you can. The tester shows every key your keyboard reports at the same moment and records your maximum rollover.
Currently registered
Gaming combinations to try
Best combination recorded
Nothing recorded yet
If you hold more keys than appear above, your keyboard is blocking the extra keys. Some operating system shortcuts, like Windows + L, cannot be captured by any website.
You are holding W to run forward, A to strafe, Shift to sprint, and you press Space to jump. Nothing happens. You did everything right, but your keyboard simply could not register one more key at the same time. That is keyboard ghosting, and it is one of the most frustrating hardware problems in gaming because it looks exactly like a missed input.
This keyboard ghosting test shows every key your board reports while you hold several at once, records the maximum it managed, and checks a set of common gaming combinations. In under a minute you know your keyboard’s real rollover and which combinations are safe to bind in your games.
How to test your keyboard for ghosting
- Click the page so it is listening to your keyboard.
- Press and hold several keys at the same time, adding one at a time. Each registered key appears in the list and lights up on the layout.
- Keep adding keys until one no longer appears. The number held just before that is your rollover for that group of keys.
- Try the combinations listed below the layout. Each turns green once all of its keys are registered together.
- Test different areas of the board, because many keyboards handle some regions better than others.
Ghosting, blocking and rollover explained
Key rollover
Rollover is the number of keys a keyboard can register at once. Two key rollover, written 2KRO, is the minimum. Many office keyboards manage six keys in some combinations and only two or three in others. N-key rollover, or NKRO, means every key can be held at the same time and all of them register.
Blocking
Most budget keyboards arrange keys in a grid of rows and columns and detect presses where a row and a column meet. Hold certain keys together and the controller cannot tell which keys are really down, so it refuses to register the extra one. That is called blocking, and it is what you usually experience as a dead key mid combo.
True ghosting
In the strict sense, ghosting is when the keyboard registers a key you did not press, a phantom created by current flowing through the grid. Modern keyboards prevent that by blocking instead, which is why most people now use the word ghosting for both problems.
How this ghosting test works
The page keeps a live list of every key that has been pressed and not yet released, using the physical key code of each one. Whenever the list grows past your previous record, the maximum and the exact combination are saved. If the browser window loses focus, the list clears so a stuck key cannot inflate your result. Combination checks simply wait until every key in a set is held at the same moment.
One limit is worth knowing. Some shortcuts are claimed by the operating system before a website sees them, so a combination that includes the Windows or Command key may never show up here. That is not a fault in your keyboard.
Understanding your result
| Max keys at once | What it means for gaming |
|---|---|
| 2 or 3 | Frequent missed inputs in movement heavy games |
| 4 to 5 | Fine for most games, occasional blocked combos |
| 6 | Classic USB 6KRO, rarely a problem in practice |
| 7 or more | NKRO or close to it, no practical limit |
The combination list matters as much as the maximum. A keyboard can reach six keys in one area and fail at four in another. If W, A, Shift and Space does not turn green, you have found exactly the kind of combo that will fail in a shooter.
What to do if your keyboard ghosts
- Rebind the failing keys. Move a critical action to a key that works in combination with your movement keys.
- Enable NKRO mode. Some gaming keyboards ship in 6KRO mode for compatibility and offer an NKRO toggle in software or through a key combination.
- Try a different port or connection. Some wireless and Bluetooth modes limit rollover that the same board supports over a cable.
- Consider an anti-ghosting keyboard. Mechanical boards with a diode for each switch support full rollover without blocking.
Laptop keyboards
Laptop keyboards are often limited, especially around the arrow keys and the right side. If you game on a laptop, WASD movement plus Shift and Space is the first combination to check.
Tips for accurate ghosting tests
- Press the keys one at a time and hold them, rather than slamming them all at once.
- Test the exact bindings you use in your favourite games, not just random groups.
- Include modifier keys like Ctrl and Shift, since they are often wired differently.
- Repeat the test after changing any keyboard mode or firmware setting.
If a key never registers even when pressed alone, the problem is not ghosting. Check it in the keyboard tester. Once your board is cleared, see how fast you are with the typing speed test, sharpen your reflexes with the reaction time test, and put your movement and aim together in the aim trainer.
Frequently asked questions
What is keyboard ghosting?
Ghosting describes a keyboard failing to register a key when several keys are held at once, or registering a key you did not press. It happens because many keyboards cannot track every key combination in their wiring grid.
How many keys should a gaming keyboard register at once?
Six keys is enough for nearly every game. N-key rollover keyboards register every key at once, which removes the question entirely.
Why do some combinations work and others fail?
Keys share rows and columns in the keyboard matrix. Combinations that land on the same lines are more likely to be blocked than keys spread across the board.
Can a USB keyboard support N-key rollover?
Yes. Older USB boot mode was limited to six keys plus modifiers, but modern USB keyboards can report every key using a different report format.
Why is the Windows key not showing?
The operating system handles many shortcuts involving the Windows or Command key before the browser receives them, so websites cannot always detect them.
What is NKRO?
N-key rollover means every key can be registered at the same time. Most gaming keyboards offer it, sometimes only in a special mode.
Why does my keyboard stop at six keys?
Many USB keyboards use a report format that limits simultaneous keys to six plus modifiers. Check for an NKRO option in its software.
Is ghosting a hardware fault?
Usually not. It is a design limit of cheaper keyboard matrices, which cannot tell some key combinations apart.
Which key combinations should gamers test?
Test the keys you actually use together, such as W, A, Shift and Space, plus any ability keys you press while moving.
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