Keyboard Test
Press any key to check if it registers. Test every key, detect ghosting, and verify N-key rollover support.
0
Keys Tested
104
Total Keys
0
Held Now
0
Max Simultaneous
How to use this test
- Press every key on your keyboard one at a time and confirm it highlights green.
- Hold multiple keys at once to test N-key rollover and check for ghosting.
- The Max Simultaneous counter shows the most keys your keyboard registered at the same time.
- Any key that does not highlight when pressed may be faulty or blocked by your OS.
- Some keys (Print Screen, Windows/Super, media keys) may be intercepted by the operating system.
- Click Reset to clear all results and start over.
Testing guide
How to use the keyboard test
This keyboard test displays a full visual layout and highlights each key the moment you press it. It verifies that every key registers correctly, measures how many keys your keyboard can handle simultaneously, and helps identify ghosting or rollover limitations.
Best for
- Testing a new or secondhand keyboard for broken, stuck, or unresponsive keys before keeping it.
- Checking N-key rollover support and finding which key combinations ghost on cheaper keyboards.
- Verifying that every key works after cleaning, modding, or swapping switches on a mechanical keyboard.
How to run the test
- 1Click anywhere on the page first so the browser has keyboard focus.
- 2Press every key one at a time and confirm each one highlights green on the visual layout.
- 3Hold multiple keys down at the same time to test N-key rollover and watch the simultaneous counter.
- 4Check the progress bar to see whether any keys were missed, then investigate those keys individually.
How to read the result
A key that does not highlight at all when pressed is either faulty or being intercepted by your operating system.
A max simultaneous count of 6 or fewer usually means the keyboard uses a matrix with limited rollover rather than true NKRO.
If pressing three keys causes a fourth unrelated key to register, that is ghosting caused by the keyboard matrix design.
Related tools and guides
Frequently asked questions
What is keyboard ghosting?
Ghosting happens when pressing a specific combination of keys causes a key you did not press to register, or causes one of the pressed keys to not register. It is caused by the electrical matrix layout inside the keyboard and is most common on inexpensive membrane keyboards.
What is N-key rollover?
N-key rollover, often abbreviated NKRO, means the keyboard can correctly register any number of keys pressed simultaneously. Full NKRO is standard on most mechanical keyboards. Budget keyboards often support only 6-key rollover over USB, sometimes called 6KRO.
Why does my Windows or Super key not register?
Many gaming keyboards have a built-in Windows key lock to prevent accidental alt-tabs during games. Check whether your keyboard has a dedicated lock switch or key combination. The operating system can also intercept certain keys before the browser sees them.
Can this test detect chattering?
This test registers whether a key fires at all, not how many times it fires per press. Chattering, where a single press registers multiple inputs, requires a separate debounce or chatter test. However, if a key highlights inconsistently, that can also indicate a contact issue.
Does this work with non-QWERTY layouts?
The visual layout shown is standard US QWERTY, but the test listens for physical key positions using KeyboardEvent.code, not characters. Every physical key registers correctly regardless of your software layout, whether you use AZERTY, Dvorak, Colemak, or any other mapping.
How many keys should my keyboard support at once?
Mechanical keyboards with NKRO can handle every key pressed simultaneously. Standard USB keyboards without NKRO typically support 6 simultaneous keys plus modifiers. For gaming, 10 or more simultaneous keys is usually enough for any realistic scenario.
Testing guide
How to use the keyboard test
This keyboard test displays a full visual layout and highlights each key the moment you press it. It verifies that every key registers correctly, measures how many keys your keyboard can handle simultaneously, and helps identify ghosting or rollover limitations.
Best for
- Testing a new or secondhand keyboard for broken, stuck, or unresponsive keys before keeping it.
- Checking N-key rollover support and finding which key combinations ghost on cheaper keyboards.
- Verifying that every key works after cleaning, modding, or swapping switches on a mechanical keyboard.
How to run the test
- 1Click anywhere on the page first so the browser has keyboard focus.
- 2Press every key one at a time and confirm each one highlights green on the visual layout.
- 3Hold multiple keys down at the same time to test N-key rollover and watch the simultaneous counter.
- 4Check the progress bar to see whether any keys were missed, then investigate those keys individually.
How to read the result
A key that does not highlight at all when pressed is either faulty or being intercepted by your operating system.
A max simultaneous count of 6 or fewer usually means the keyboard uses a matrix with limited rollover rather than true NKRO.
If pressing three keys causes a fourth unrelated key to register, that is ghosting caused by the keyboard matrix design.
Related tools and guides
Frequently asked questions
What is keyboard ghosting?
Ghosting happens when pressing a specific combination of keys causes a key you did not press to register, or causes one of the pressed keys to not register. It is caused by the electrical matrix layout inside the keyboard and is most common on inexpensive membrane keyboards.
What is N-key rollover?
N-key rollover, often abbreviated NKRO, means the keyboard can correctly register any number of keys pressed simultaneously. Full NKRO is standard on most mechanical keyboards. Budget keyboards often support only 6-key rollover over USB, sometimes called 6KRO.
Why does my Windows or Super key not register?
Many gaming keyboards have a built-in Windows key lock to prevent accidental alt-tabs during games. Check whether your keyboard has a dedicated lock switch or key combination. The operating system can also intercept certain keys before the browser sees them.
Can this test detect chattering?
This test registers whether a key fires at all, not how many times it fires per press. Chattering, where a single press registers multiple inputs, requires a separate debounce or chatter test. However, if a key highlights inconsistently, that can also indicate a contact issue.
Does this work with non-QWERTY layouts?
The visual layout shown is standard US QWERTY, but the test listens for physical key positions using KeyboardEvent.code, not characters. Every physical key registers correctly regardless of your software layout, whether you use AZERTY, Dvorak, Colemak, or any other mapping.
How many keys should my keyboard support at once?
Mechanical keyboards with NKRO can handle every key pressed simultaneously. Standard USB keyboards without NKRO typically support 6 simultaneous keys plus modifiers. For gaming, 10 or more simultaneous keys is usually enough for any realistic scenario.