# Keyboard tester

> Test every key of a laptop or desktop keyboard in your browser. Keys light up as you press them; see key codes, stuck keys and how many keys register at once.

URL: https://tools.cuelark.com/keyboard-test
Publisher: Cuelark Team (https://cuelark.com)
Updated: 2026-11-10
Price: free, no sign-up
Privacy: runs in the browser; files are not uploaded

Click the keyboard below and press every key: each one lights up while held and turns green once it has worked. Find dead or sticky keys, check a new or second-hand laptop, and see how many keys register at the same time.

## How to use it

1. Click the keyboard area so it has focus.
2. Press each key once. Working keys turn green; a key that stays blue while released is sticking.
3. Hold several keys together to see how many register at once (rollover), then press Reset to test again.

## Details

- **Layouts:** Full size with numpad and navigation keys, or laptop / tenkeyless
- **Shows:** Key, code and keyCode of the last key, keys tested out of total, and the most keys held at once
- **Detects:** Dead keys (never turn green), sticky keys (stay lit), double presses (watch the log), limited rollover
- **Cannot see:** Fn, media keys and system shortcuts handled by the operating system before the browser

## Questions

### Is anything recorded or sent?

No. The page reads the device inside this tab and shows the result. Nothing is stored or uploaded; close the tab or press Stop and access ends.

### A key does not light up. Is it broken?

If other keys work, the key is likely dirty or worn: try compressed air, or check it in another app. Fn, Win+L, some laptop F-keys and media keys never reach a web page, so they cannot light up here even when they work.

### What does 'most keys held at once' tell me?

It is the rollover: how many simultaneous keys the keyboard reports. Gaming keyboards often handle 6 or more; many laptop keyboards stop at 2–4 for some combinations, which is called ghosting.

### Can I test a phone or tablet keyboard?

Only a physical keyboard connected to the phone or tablet. On-screen keyboards send text, not key events, so most keys cannot be shown.

### Why do the keys show a US layout?

Keys are matched by physical position (KeyboardEvent.code), which is named after the US layout. On other layouts the positions still light up correctly; the Last key box shows the character your layout produces.

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