Keyboard Tester: Check Every Key Online
Press any key and it lights up on the full-size layout. Keys you have already tested stay marked, so dead or sticky keys stand out right away.
Connect a physical keyboard for this test. On-screen keyboards do not report key codes.
Keys outside this layout (media, ISO, macro keys)
A single dead key is surprisingly easy to miss. You might not touch Scroll Lock or the right Alt for weeks, and a sticky F5 only matters the day you need it. This keyboard tester shows a full keyboard on screen and lights up every key you press, so you can sweep the whole board in a couple of minutes and know for certain which keys work.
Keys you have tested stay outlined, keys you are holding right now glow, and anything your keyboard sends that is not on the standard layout, such as media keys or the extra key on ISO boards, appears in its own list. It works with wired, wireless and Bluetooth keyboards, mechanical or membrane, with no download.
How to test your keyboard
- Click anywhere on this page so the browser is listening to your keyboard.
- Press every key once, row by row, from Escape across to the number pad.
- Watch the on-screen layout. Each key should turn to its tested colour the moment you press it.
- Check the counter for keys tested. When every key on your layout is outlined, the switches and wiring are working.
- Press Reset keys to start another pass, for example after cleaning the keyboard.
The last key, code and legacy key code panels show exactly what your keyboard reported for the most recent press, which is handy when a key behaves strangely in a specific app.
How the keyboard tester detects keys
Physical key codes, not characters
Every key press gives the browser two pieces of information: the character it types, which depends on your language layout, and a code for the physical key position. The tester relies on the physical code. That is why it correctly tells left Shift from right Shift, and number pad digits from the number row, and why it works whether your system is set to QWERTY, AZERTY or another layout.
Press and release
Keys light up on press and dim on release, so you can also see whether a key gets stuck. If a key stays lit after you let go, the switch may not be returning fully, or the keyup signal is being lost.
What a browser cannot capture
Some keys are handled by the operating system before any website sees them. The Windows key combinations, Fn on most laptops, and certain vendor media keys may not register. That is a system limit, not a keyboard fault.
Reading your results
- A key never lights up. The switch, the circuit or the keycap stem may be faulty. Remove the keycap, check for debris, and test again.
- A key lights up only when pressed hard. Common on membrane keyboards with worn domes, and on dirty mechanical switches.
- Pressing one key lights another. The key is remapped in software or the keyboard layout setting does not match the physical board.
- A key registers twice. Mechanical switches can chatter like mouse buttons. Watch the total presses counter while tapping it once.
- Keys stop working only when several are held. That is ghosting or limited rollover, which needs a different test.
For that last case, use the keyboard ghosting test. It shows how many keys your board can register at once and checks common gaming combinations like W, A and Shift with Space.
Mechanical versus membrane failures
The two main keyboard types fail in different ways, and knowing which you own points to the fix. Membrane boards use a rubber dome that pushes two plastic sheets together, so worn keys start needing more force before they register, and a spill can bridge contacts across a whole region. Mechanical boards give each key its own switch. A failing switch usually affects only that key, often as chatter or an intermittent press, and on hot swap boards it can be replaced in seconds without solder.
When to run a keyboard test
Buying used or refurbished
A full sweep before the return window closes can save you from a board with a dead key in a rarely used corner.
After a spill or cleaning
Liquid damage often shows up days later as a whole row or column failing, because keys share circuit lines.
Before a match or exam
Thirty seconds of testing is cheap insurance before anything that depends on your keyboard.
Tips for fixing common keyboard problems
- Turn the keyboard upside down and shake it gently, or use compressed air between the keys.
- For mechanical boards, pull the keycap and press the bare switch to rule out a cracked stem.
- Try a different USB port and cable, and replace batteries on wireless boards.
- Reset or close macro software that might remap keys.
- Update the keyboard firmware if the manufacturer offers it, since some updates fix debounce and wireless dropouts.
- Test the keyboard on another computer to separate a hardware fault from a driver or settings problem.
Once every key checks out, put the board to work. The typing speed test and WPM test measure how fast you type, and the spacebar counter is a fun check for the biggest switch on your board. Your mouse deserves the same treatment in the mouse test.
Frequently asked questions
How do I check if all my keyboard keys work?
Open the keyboard tester, click the page, and press every key once. Each working key changes colour on the on-screen layout. Any key that stays grey did not register.
Why is my Fn key not detected?
On most laptops and many compact keyboards, Fn is handled inside the keyboard itself and never sent to the computer, so no website or app can see it.
Does the tester work with non-English layouts?
Yes. It identifies keys by their physical position, so AZERTY, QWERTZ and other layouts are detected correctly even though the labels on the layout follow a US arrangement.
What are the keys listed outside the layout?
Those are keys your keyboard sent that are not on the standard layout shown, such as media controls, the extra ISO key next to left Shift, or macro keys.
Can I test a laptop keyboard?
Yes. Laptop keyboards work the same way, although some function row keys may be reserved by the system.
Can this test a laptop keyboard?
Yes. Laptop keyboards work the same way. Some function keys are handled by the laptop itself and may not reach the browser.
Why does the Windows key or Fn not show?
The operating system often captures the Windows key, and Fn usually never leaves the keyboard. That is normal behaviour, not a fault.
How do I test a key that sometimes does not register?
Press it repeatedly with different pressure and angles. Keys that only work with a firm, central press often need cleaning or a new switch.
Does it support non-US layouts?
Keys are detected by physical position, so they still light up on other layouts even if the printed labels differ.
Related tools
Every key works. How many work at once?
Cheap boards drop keys the moment you hold several together. Check your rollover before it costs you a jump or a reload.