Keyboard Test – Check Every Key, Rollover & Chatter Online
Press any keyReady
- Runs locally, nothing uploaded
- Allow permissions when asked
- Some sensors need a phone
- Runs inside your browser
- No upload, no account
- Nothing saved after you close
Online keyboard tester with rollover and chatter check
Press every key on your keyboard; working keys turn green. The log shows key codes, and the rollover counter shows how many keys register at once.
Key rollover and ghosting
Cheap keyboards may only register 2–3 simultaneous keys or ghost extra keys.
Key chatter
A worn switch can register one press as two.
Keys that cannot be tested
Fn, some media keys and OS shortcuts (like Windows key combos) are handled by the system before the browser sees them.
How to Use the
Keyboard Test
- 01
Focus
click the page so it receives key presses.
- 02
Press
hit every key; tested keys turn green.
- 03
Rollover
hold several keys to see how many register at once.
- 04
Chatter
a warning appears if one press registers twice.
Key rollover and ghosting
Cheap keyboards may only register 2–3 simultaneous keys or ghost extra keys. Gaming keyboards usually support 6KRO or NKRO.
Key chatter
A worn switch can register one press as two. If the log flags chatter repeatedly, clean or replace the switch.
Keys that cannot be tested
Fn, some media keys and OS shortcuts (like Windows key combos) are handled by the system before the browser sees them.
Keyboard layout notes
The navigation keys below the layout
Arrow, Insert, Delete, Home, End and Page keys sit in the last row for compact layouts.
How to test every key
- Click inside the page so it has focus.
- Press each key once; it lights up when detected.
- Hold combinations you use (for example W+A+Shift+Space) to check rollover.
- Watch for keys that light twice for one press: that is switch chatter.
Interpreting the result
| What you see | Meaning |
|---|---|
| Key never lights | Dead switch, dirt, or a remapping/Fn-lock |
| Lights twice per press | Chatter; clean or replace the switch |
| Some combos drop a key | Ghosting/rollover limit (explained) |
| Wrong key lights | Layout setting differs from the keycaps |
Related guides and fixes
Learn more in these guides: Webcam not working, Keyboard ghosting explained, Fix mouse double clicking, Webcam settings.
Frequently Asked Questions
Q.Why does Fn not light?
Fn is handled in the keyboard hardware.
Q.Laptop layout differs?
Missing keys simply stay grey.
Q.Is anything uploaded?
No. Everything runs locally in your browser.
Q.Which keyboard layouts is this test designed for?
The on-screen layout is a standard US-style layout, but any key you press is detected by its key code, so other layouts work too; the label shown may differ from your keycap.
Q.Some keys like Print Screen or the Windows key don't light up. Why?
The operating system intercepts some keys before the browser sees them. That does not mean the key is broken.