Start capture, then press and release a key.
On mobile, connect a physical keyboard.
Press a key to see its physical code and the character reported by your browser.
Save up to five summaries in this browser. Each contains the layout and aggregate measurements.
No saved scans yet.
Select Start capture or click the test area, then press and release each key on your physical keyboard. The on-screen key lights up while the browser sees it held, then stays marked as tested after release. Use Keys still to test to find positions missing from the scan.
On a phone or tablet, connect a physical keyboard to check its keys. The on-screen typing keyboard may report text without the physical key positions this test uses.
Full size, TKL, and 60% show common US ANSI layouts. Choose the closest match to the size of your keyboard. If your keycaps use another layout, compare physical positions and check the reported key value in the log. Extra keys can appear under Keys detected outside this layout.
The Fn key often works inside the keyboard itself. System shortcuts and media keys can also be handled before the browser sees them. Try ordinary keys and modifiers to confirm that the page is receiving input.
Tap and release the suspect key several times with the test area focused. Compare it with a nearby key. Look for missed highlights, a key that stays marked as held after release, or several presses from one quick tap.
Holding a key down usually triggers normal auto-repeat. If one short tap keeps producing extra events, repeat the check in another app or with another USB port or connection. Change one thing at a time so you can see what affects the symptom.
Test the keys individually, then hold them together, such as W + A + Shift. Watch which keys light up and release them one at a time. If a key registers by itself and drops out in that combination, try the same combination again.
Peak keys held is the largest number of keys the browser saw held together in this scan. It describes the rollover for the combinations you tried.
The log shows the key value and its physical position code, such as A and KeyA. Hold duration runs from the first captured press to release. The Repeats column counts extra events the browser reports while you keep that key down.
Browser event delay estimates the time between a key event’s timestamp and when this page handles it. Browser activity can change this delay. Measuring the time from a physical press to a response on screen requires a dedicated latency setup.
You can test Esc in the test area and use Tab to leave. If focus moves away before you release a held key, the log marks that press as Interrupted.
The page processes key events in this browser. Save scan keeps up to five summaries here with the scan counts and settings. Share summary shares the number of tested keys, layout, and page link through your browser’s share menu or copies them to the clipboard.
Choose Export JSON if you want a file with the current diagnostic events. Review that file before sharing it.