Press any physical key to audit broken switches, test N-Key Rollover limits, catch double-click switch chatter (<35ms), and inspect live JavaScript KeyboardEvent codes.
Start typing on your physical keyboard to stream hardware codes and inspect millisecond switch release-to-repress intervals.
N-Key Rollover measures how many simultaneous keys your keyboard registers accurately without dropping signals (ghosting). Hold 6 to 10 random keys at once on the tester above—standard laptops stop near 2–6 keys, whereas quality mechanical boards support full NKRO over USB.
Key chatter happens when oxidized metal contacts inside a mechanical switch bounce twice from a single press, producing double letters like “eerror”. Our diagnostic timer flags any repeated downstroke arriving faster than 35ms after release.
Use event.code when key position matters (shortcuts, games, Dvorak/AZERTY physical layouts) and event.key when the typed character value matters. Notice how TypingCompiler tracks physical positions independently of Shift state.
