Keyboard Tester

Test all keyboard keys and check key input information

⌨️

Press any key

Modifier Keys

Ctrl
Alt
Shift
Meta

Key History (Last 10)

No keys pressed yet

Visual Keyboard

Esc
F1
F2
F3
F4
F5
F6
F7
F8
F9
F10
F11
F12
`
1
2
3
4
5
6
7
8
9
0
-
=
Tab
Q
W
E
R
T
Y
U
I
O
P
[
]
\
Caps
A
S
D
F
G
H
J
K
L
;
'
Shift
Z
X
C
V
B
N
M
,
.
/
Shift
Ctrl
Alt
Space
Alt
Ctrl

What is Keyboard Tester?

A keyboard tester is a tool to check if each key on your keyboard works correctly. When you press a key, it displays the key information (key, code, keyCode) and modifier key states in real-time.

Key Features

  • Real-time key input detection
  • Display key name, code, and keyCode
  • Modifier key (Ctrl, Alt, Shift, Meta) status
  • Key combination detection (e.g., Ctrl+Shift+A)
  • Key input history tracking
  • Visual keyboard layout

How to Use

Press any key on your keyboard. The key information will be displayed in real-time. Press multiple keys simultaneously to see key combinations.

Frequently Asked Questions

A keyboard tester is used to check if specific keys on your keyboard are working correctly. It is useful for checking that all keys work normally after buying a new keyboard, diagnosing issues where a key doesn't respond during gaming, and verifying key recovery after cleaning your keyboard.
A ghost key is a phenomenon where pressing multiple keys simultaneously causes a key that was not actually pressed to be detected as pressed. It occurs mainly on membrane keyboards, and ghost key issues can cause unintended inputs during gaming or fast typing.
Hold down multiple keys simultaneously and this tool will display all currently pressed keys. The number of keys recognized at the same time indicates the rollover performance of your keyboard. 6KRO means 6 simultaneous keys, while NKRO means all keys can be recognized at once.
Mechanical keyboards have an independent switch for each key, providing a distinct tactile feel and high durability. Membrane keyboards use a rubber dome mechanism, making them cheaper and quieter, but more prone to ghost key issues. Mechanical keyboards generally provide better NKRO support.

Why Keyboard Testing Matters

Why You Should Check Keyboard Performance

The keyboard is a core input device for any computer, and a single malfunctioning key can significantly reduce work efficiency. Programmers, writers, and gamers are especially sensitive to keyboard performance. Use this tool to test a keyboard before purchasing or to diagnose the condition of your current keyboard.

What Is N-Key Rollover (NKRO)?

N-Key Rollover (NKRO) indicates how many keys a keyboard can accurately detect simultaneously. Standard membrane keyboards typically support 3–6KRO, while high-end mechanical keyboards support full NKRO, recognizing every key pressed at the same time. High rollover support is essential for fast musical performance or complex gaming inputs.

This calculator is provided for informational purposes only.

Results are estimates and may differ from actual amounts.

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