Select a combination
Choose a preset or add physical keys to a custom combination. Shift in a preset accepts either left or right Shift; custom keys use their exact physical codes.
FREE · LOCAL · PHYSICAL KEYBOARD
Keyboard Ghosting Test
Test guided or custom combinations, then confirm the keys you held together.
Build a custom combination
Add the physical keys you want to hold together.
CURRENT KEYS HELD0
MAX SIMULTANEOUSLY DETECTED0
COMBINATION TESTS COMPLETED0
COMBINATIONS WITH MISSING INPUTS0
EXPECTED KEYSW + A + Space
DETECTED TOGETHER (BEST OBSERVATION)None
NOT YET DETECTED TOGETHERW + A + Space
ADDITIONAL OBSERVED KEYS (UNCERTAIN)None
Choose a combination and click Start, or focus here to observe held keys.
Held now: None
Largest simultaneous set this attempt: None
Did you hold all expected keys together?
Only confirm if you actually held every specified physical key at the same time.
Confirmed combinations
Last 20 results. Session counters include every confirmed attempt.
| Expected | Best detected together | Missing inputs | Additional inputs |
|---|---|---|---|
| No confirmed attempts yet. | |||
Recent keydown / keyup events
| Physical code | Event |
|---|
Test only with a physical keyboard. Do not type passwords or sensitive information. Events stay in page memory. Fn, media keys, and OS-reserved shortcuts may not reach your browser.
THE PROCESS
How to Use
Hold the keys together
Click Start and hold every expected key at the same time. The best observation is one simultaneous set, not a union of keys pressed at different times.
Finish and confirm
Click Finish, then confirm whether you actually held all expected keys together. Only confirmed attempts enter the completed and missing-input statistics.
WHAT THE NUMBERS MEAN
How to Interpret Results
Some Expected Keys Were Not Detected means the best simultaneous observation was incomplete after you confirmed the intended physical combination. Browser or OS shortcuts, incorrect timing, and keyboard blocking can all affect this result.
Ghosting can produce an unexpected additional key. Blocking or masking means an expected key fails to reach the browser. Additional observed keys are uncertain: you may also have pressed them yourself.
This tool measures browser-received inputs. It cannot certify hardware NKRO, prove hardware ghosting, or see a key that the operating system intercepts. Compare repeated attempts and a second device before drawing conclusions.
GOOD TO KNOW
Frequently Asked Questions
Why do I need to confirm the combination?
The browser cannot know which physical keys you intended to hold. Until you confirm that all expected keys were held together, a missing input is only an unfinished observation.
Can keys pressed one after another pass a combination test?
No. Results use the largest matching set seen at one moment. Separate presses are never added together to claim simultaneous detection.
What happens if I switch tabs or lose window focus?
Held-key highlighting is cleared and the current guided attempt is interrupted. Restart the attempt before confirming a result. Clicking Finish within this page preserves the best observation for confirmation.
Can I test more than the preset combinations?
Yes. Add exact physical keys from the custom selector, remove or clear them, and use that combination. The display and report distinguish physical left/right modifiers and numpad codes.