Keyboard Test: Online Key Tester for Every Key

Free online keyboard test: press every key and watch it light up on a full, TKL or laptop layout (ANSI/ISO, Windows/Mac). Detect dead, stuck and chattering keys, test N-key rollover and ghosting, and read key codes live. No download.

Built and maintained by Shehzad Munir ·

Keyboard Test
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How to test a keyboard online

A free online keyboard tester that checks every key on full-size, TKL and laptop keyboards in ANSI or ISO layouts, with Windows or Mac labels. Keys light up as you press them, turn green once tested and show a press count, so dead, stuck and chattering keys stand out instantly. You also get live key, code and keyCode readouts, press duration, a modifier and lock-key panel, an N-key rollover counter, automatic double-fire (chatter) detection, a heatmap, a live event log and a copyable test report. It all runs locally in your browser.

Pick the layout that matches your keyboard, click anywhere outside a text box, and press every key once. Keys light up while held and turn green when they've been registered, and the coverage bar fills toward 100%. Any key that never lights up is dead or disconnected; a key that stays highlighted after you release it is sticking. Because the tester reads the same keyboard events your apps receive, what you see is exactly what the operating system is reporting.

Features

  • Three Layouts, Two Standards: Full-size 100% with numpad, TKL 80% and laptop/75%, each in ANSI or ISO, with Windows or Mac key labels.
  • Realistic Visual Keyboard: Keys light up while held, turn green once tested and show a press counter; it scales to fit any screen.
  • Automatic Chatter Detection: Flags any key that re-fires within 20-80 ms of being released, the classic sign of a worn or dirty switch.
  • N-Key Rollover & Ghosting Test: Hold several keys and see the maximum registered at once (e.g. 6KRO) plus the exact keys being held.
  • Live Key Readout: event.key, event.code, keyCode, key location (left/right/numpad) and press duration in milliseconds.
  • Modifier & Lock Panel: Live Shift, Ctrl, Alt, AltGr, Meta/Cmd, Caps Lock, Num Lock and Scroll Lock state.
  • Keyboard Lock Mode: Fullscreen lock (Chrome/Edge) captures Esc, Tab, Alt and Windows/Cmd keys so even they can be tested.
  • Heatmap, Event Log & Report: Colour keys by press count, stream every keydown/keyup, list untested keys and copy a test report.
  • Extra Keys Detected: Media, F13-F24 and international keys not on the drawing are listed so nothing goes unnoticed.
  • Layout-Independent & Private: Uses physical key codes, so it works on QWERTY, AZERTY, QWERTZ and Dvorak; nothing is recorded or uploaded.

How to use Keyboard Test

  1. 1

    Pick your keyboard

    Choose Full, TKL or Laptop/75%, then ANSI or ISO and Windows or Mac so the drawing matches the keyboard in front of you.

  2. 2

    Press every key

    Click outside any text box, then press keys one at a time. Each key turns blue while held and green once tested; the coverage bar tracks progress.

  3. 3

    Check for dead or stuck keys

    Any key that never lights up is not registering. A key that stays blue after release is sticking. Use the Untested keys list to find stragglers.

  4. 4

    Look for chatter

    Tap each key normally. If a single press ever counts twice, the key is flagged amber with a warning; adjust the chatter threshold if needed.

  5. 5

    Test rollover and save a report

    Hold combinations like W + A + S + D + Shift + Space to measure N-key rollover, then use Copy report to save or share the results.

Common use cases

  • Find dead, stuck or unresponsive keys before replacing a keyboard or laptop
  • Check a new or second-hand mechanical keyboard, including every numpad and function key
  • Diagnose double-typing (switch chatter) automatically instead of guessing
  • Verify N-key rollover and anti-ghosting on a gaming keyboard
  • Test a laptop keyboard before a warranty claim or return, with a copyable report
  • Look up event.code, key and keyCode values for key remapping or web development
  • Confirm ISO keys such as the extra \ key and the tall Enter key work on UK/EU keyboards

Detailed guide

Automatic keyboard chatter (double-typing) detection

Keyboard chatter is when one physical press registers as two or more, so you get 'hhello' or doubled spaces. It's the most common fault on worn mechanical switches. This tester measures the gap between each key's release and its next press; if the key fires again within the chatter threshold (40 ms by default, adjustable from 20 to 80 ms) it's flagged amber and counted in Chatter alerts. Human double taps are almost always slower than 60-80 ms, so a flag at 20-40 ms is a strong sign of a faulty switch.

Check your mouse for double-clicking

N-key rollover (NKRO) and ghosting explained

Rollover is how many keys a keyboard can report at the same time. Basic membrane keyboards often cap at two or three keys in certain combinations, which causes ghosting: presses that silently disappear or phantom keys that appear. Gaming keyboards usually offer 6-key rollover over USB or full NKRO. Hold a cluster of keys such as W + A + S + D + Shift + Space: the Keys held readout lists what's registered right now and Max rollover records your best, shown as e.g. 6KRO. Note that some laptops and USB boards limit rollover in specific key combinations only, so test the combos you actually use in games.

Full-size, TKL, laptop, ANSI and ISO layouts

Full-size keyboards include the navigation cluster and numpad (about 104-105 keys), TKL (tenkeyless, 80%) drops the numpad, and laptop or 75% layouts keep the arrow keys but remove most of the navigation cluster. ANSI is the US standard with a wide Enter key and long left Shift; ISO, used in the UK and much of Europe, has a tall Enter key, a # key beside it and an extra \ key next to a short left Shift. Pick the matching combination and the tester counts coverage only for the keys your board actually has. Switch to Mac labels for ⌘ Command, ⌥ Option and ⌃ Control.

Key codes for developers: key, code and keyCode

event.key is the character produced (it changes with Shift and your layout), event.code identifies the physical key (KeyA is always the same position, even on AZERTY), and keyCode is the legacy numeric code still used by older scripts. The live readout and event log show all three, along with key location (left, right or numpad) and whether the event is an auto-repeat, which makes the tool handy for building shortcuts, games and remapping configs.

Test your typing speedTest a game controller

Testing Esc, Windows, Cmd and Print Screen keys

Browsers and operating systems reserve some keys: Esc exits fullscreen, the Windows/Cmd key opens system menus, and Print Screen often fires only on release. Use Lock mode in Chrome or Edge: it enters fullscreen and uses the Keyboard Lock API so Esc, Tab, Alt and the Windows/Cmd key are sent to the tester instead (hold Esc for two seconds to exit). Print Screen is counted on key release. Media keys, F13-F24 and other extra keys appear under Extra keys detected.

Frequently asked questions

How do I test my keyboard online?

Choose the layout that matches your keyboard, click anywhere outside a text box, then press each key. Keys light up while pressed and turn green once tested. Any key that never lights up isn't registering. Nothing to install.

How do I know if a key is dead or stuck?

A dead key never lights up and the coverage counter doesn't move when you press it. A stuck key stays highlighted after you let go, and the Keys held readout keeps listing it.

How does the chatter (double-typing) detection work?

The tester times the gap between a key's release and its next press. If the key fires again faster than the chatter threshold (40 ms by default), which is quicker than a human can re-press, it's flagged amber and counted as a possible double-fire.

What is N-key rollover and how do I test it?

N-key rollover (NKRO) is how many keys a keyboard can register at once. Hold several keys together, for example W + A + S + D + Shift + Space, and watch Keys held and Max rollover. Basic keyboards often stop at 2-3 keys; gaming keyboards reach 6KRO or full NKRO.

Can I test the Windows, Cmd, Esc and Print Screen keys?

Yes. Use Lock mode in Chrome or Edge, which enters fullscreen and captures Esc, Tab, Alt and the Windows/Cmd key. Print Screen is counted when it's released, since Windows only sends that event.

Does it work with ISO, Mac and laptop keyboards?

Yes. Switch between Full, TKL and Laptop/75% layouts, ANSI or ISO, and Windows or Mac labels. Keys are matched by physical position, so AZERTY, QWERTZ and Dvorak layouts work too.

Why doesn't my Fn key light up?

The Fn key is handled inside the keyboard's firmware and is never sent to the computer, so no website or app can detect it. Test it by holding Fn with another key (for example Fn + F5) and checking that the expected function key registers.

Is my typing recorded?

No. Key events are processed locally to light up the keys. Nothing is logged or uploaded; only your tested-key progress and layout choice are saved in your browser.

Can I test a laptop keyboard before returning it?

Yes. Select Laptop/75%, press every key until coverage reaches 100%, check the chatter panel, then use Copy report to keep a record of which keys failed.

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