Multi-key observation
Keyboard Ghosting Test
Hold two, three or more keys at once and watch exactly which combinations the browser receives — plus an honest explanation of why “missing” keys cannot be blamed on any single cause.
Click this area, then hold two or more keys down at the same time.
Combinations the browser received
Nothing recorded yet. Each new key you press without releasing the previous ones appears here as one combination.
A key you are physically holding that never appears here was dropped somewhere between the keyboard and the browser. This page cannot tell whether that happened in the keyboard hardware, the operating system or the browser.
How to test
A simple three-key routine
You can hold any keys you like; this routine just makes the result easy to read.
What this cannot tell you
Ghosting, blocking, and the limits of a web page
Keyboard “ghosting” and “key blocking” are hardware behaviours: some key matrices cannot register certain keys held together, so the keyboard sends nothing or even a wrong key. But an operating system or browser can also filter combinations, and from inside a web page those cases look exactly the same. This tool reports what arrived — nothing more.
That is why you will find no pass/fail badge and no rollover number here. If a combination matters to you (a game move, a shortcut), the practical test is whether the browser receives it — which is precisely what this page shows.
Questions
Ghosting test FAQ
What does this ghosting test show?
It shows which keys the browser sees while you hold several of them at once: the keys held right now, every combination that was received as you added keys, and the largest number of keys the browser received simultaneously. It is an observation tool — it does not judge or grade your keyboard.
How do I run a multi-key test?
Click the observation area, then press and hold a key. Without releasing it, press and hold a second, then a third, and so on. Each new key you add without releasing the others is recorded as one combination. Release everything, then press Reset to start a clean round.
A key I held never showed up — is my keyboard ghosting?
Not necessarily, and this tool cannot tell. A missing key means the press was dropped somewhere between the keyboard, the operating system and the browser. True hardware ghosting or key blocking, OS-level filtering, and browser behaviour can all look identical from inside a web page, so no tool like this can attribute the cause.
Why is there no pass or fail result?
Because “received N keys at once” is a fact about this browser session, not a verdict about your hardware. Marketing claims like “N-key rollover” are measured differently by every maker. This page shows you exactly what was received and leaves the interpretation to you.
How many keys should I be able to hold at once?
There is no single right number. Many keyboards deliver at least 6 non-modifier keys at once, but the count can differ per key group and per device, and some combinations are filtered before the browser. Try a few different key groups if you want a fuller picture.
Does this work with on-screen or touch keyboards?
Physical keyboards send press-and-hold events naturally. Touch screens generally cannot hold several keys at once, so on touch-only devices this tool will honestly show nothing rather than fake a result.
Are my keystrokes recorded or sent anywhere?
No. Everything happens in your browser and disappears when you leave or reset the page. There is no analytics on this site and no key data is transmitted — you can confirm with your browser's network panel.