What does this test check?
The keyboard test verifies that your keyboard can register input correctly through the browser. It checks:
- Key detection — every key press is detected and displayed in real time with its key code and label.
- Modifier keys — Shift, Control, Alt, Meta, and Caps Lock are shown separately so you can verify they activate correctly.
- Key codes — the physical key position (key code) and the character produced (key value) are both shown, which is useful for diagnosing layout issues.
- Simultaneous presses — test whether your keyboard supports multi-key detection (n-key rollover).
How the keyboard test works
- Click on the test area or press any key to start.
- Press any key on your keyboard — the test will display the key name, code, and whether any modifiers are active.
- Press multiple keys simultaneously to test n-key rollover.
- Check the modifier indicators to verify Shift, Ctrl, Alt, and Meta keys are working.
Key codes vs. key values
The KeyboardEvent API provides two important values:
- Key code— the physical position of the key on the keyboard. Pressing "A" always returns the same key code regardless of keyboard layout.
- Key value — the character or action the key produces. This changes with keyboard layout and modifier state.
Troubleshooting unresponsive keys
If keys are not registering:
- Make sure the browser window is focused (click inside the test area).
- Try a different browser to rule out browser-specific issues.
- For physical keyboards, check the USB connection or try a different port.
- Clean around the key switch to remove debris that may block the contact.
- If multiple keys fail, the keyboard controller may be the issue.
Browser keyboard limitations
Browser keyboard events have inherent limitations:
- System shortcuts — Key combinations like Alt+Tab, Cmd+Space, or Ctrl+Alt+Del are intercepted by the operating system before reaching the browser.
- Browser shortcuts — Some key combinations are reserved by the browser (e.g., Ctrl+T for new tab, F5 for refresh) and cannot be captured by web pages.
- Virtual keyboards — On-screen keyboards on phones and tablets may not fire keydown events for all keys, and some keys may be absent entirely.
- Hardware limitations — This test verifies that the browser receives keyboard events. It cannot diagnose physical hardware issues such as stuck or broken keys.