Keyboard Tester

Press any key to test it. Green = tested, Blue = currently held.

Not tested
Pressed
Tested
0 keys tested

Navigation & Arrows

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Diagnose Stuck Keys

Find keys that are physically stuck, registering without being pressed, or not responding at all.

Test After Repair

After cleaning or replacing keys, verify every key registers correctly before putting the keyboard back to use.

Check New Keyboard

Quickly verify all keys work on a new or used keyboard purchase before your return window closes.

About the Keyboard Tester

The keyboard tester is a free browser-based tool that lets you check every key on your keyboard in real time. Press any key and it lights up on a visual keyboard map — blue while held, green after release — so you can instantly confirm whether each key is registering correctly. No downloads, drivers, or software installation required.

  • Visual 104-key QWERTY layout including function row, numpad, and navigation cluster
  • Real-time key state: idle (gray), pressed (blue), and tested (green)
  • Key history strip showing the last 20 keys pressed with their key codes
  • Multi-key simultaneous press support — useful for testing n-key rollover (NKRO)
  • Displays the raw key value and code for the last pressed key
  • Works entirely in your browser — no keystrokes are sent to any server

How to Use the Keyboard Tester

  1. 1

    Click anywhere on the page

    Make sure the page has keyboard focus by clicking once inside it. This ensures your keystrokes are captured by the tester rather than the browser address bar or another app.

  2. 2

    Press any key

    The key lights up blue the moment you press it. The "Last Key Pressed" panel shows the key character and its internal code name (e.g., KeyA, F5, ArrowLeft).

  3. 3

    Release the key

    The key turns green to confirm it registered both press and release. A key that stays blue after you lift your finger may be physically stuck or the release event was blocked.

  4. 4

    Work through the entire keyboard

    Press every key row by row. Any key that stays gray after you press it is not registering. The counter at the top tracks how many keys have been tested so far.

  5. 5

    Reset and re-test if needed

    Click the Reset button to clear all key states and start a fresh test. Useful when re-testing after cleaning or swapping a keycap.

Tip: Some keys like Fn, F5, and F11 may be intercepted by your OS or browser before they reach this page. Try pressing F11 to enter fullscreen first, which reduces browser interception of function keys.

Frequently Asked Questions

How does this keyboard tester work?

It listens for browser keydown and keyup events. When you press a key, it lights up blue. When you release it, it turns green — confirming the key registered both press and release correctly.

Why does a key show as untested after I pressed it?

Some keys like Fn, or keys that trigger browser shortcuts (e.g., F5 to refresh) may be intercepted by the OS or browser before they reach this page. Try using fullscreen mode or a different browser.

Can I test multiple keys at once?

Yes. Hold multiple keys simultaneously and each one will light up blue. This also helps test n-key rollover (NKRO) — how many keys your keyboard can register at the same time.

Is any data sent to a server?

No. Everything runs entirely in your browser using JavaScript event listeners. No keystrokes are logged, stored, or transmitted anywhere.

My keyboard has different keys — why aren't they shown?

This layout shows a standard 104-key US QWERTY keyboard. Media keys, volume knobs, and macro keys vary by manufacturer and may use proprietary drivers not accessible via the browser keyboard API.

What is key ghosting?

Ghosting occurs when pressing multiple keys causes the keyboard to falsely report an additional key being pressed. Gaming keyboards with anti-ghosting or NKRO technology prevent this. Press multiple keys to test yours.