What NKRO claims mean
A true NKRO keyboard is designed to avoid matrix limits. Firmware and OS handling still affect what a browser test sees.
N-Key Rollover Test
NKRO usually means a keyboard claims to report every key independently. This test shows how many keys the browser currently detects so you can compare with that claim.
Mobile note: N-key rollover checking needs a physical keyboard.
esc F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12
` 1 2 3 4 5 6 7 8 9 0 - = backspace
tab Q W E R T Y U I O P [ ] \
caps A S D F G H J K L ; ' enter
shift Z X C V B N M , . / shift
ctrl win alt space alt win menu ctrl
Detected state
Browser view Current held 0
Maximum held 0
Held keys None
Limitations: this panel reports keyboard events delivered by the operating system to
this browser tab. It cannot measure hardware matrix behavior, firmware promises, USB polling, or true
physical latency.
About this test
Build a broad chord
Hold letters across both hands, add digits, then add modifiers. Each step shows whether the detected count stays equal to the number of keys you hold.
Treat the result as evidence
A high detected count is consistent with NKRO, but a browser test cannot certify hardware. Use it as one signal among several.
Related tools
Related guides
Can I prove my keyboard is NKRO in a browser?
No. The browser can only report the key events the OS delivers. That is useful evidence but not a hardware certification.
Why does USB polling matter?
USB report rate limits how often key states are sent. A fast chord can briefly exceed the report rate even on capable hardware.
What is N-key rollover and why does it matter?
N-key rollover (NKRO) means each keypress is registered independently, even when many keys are pressed at once. It matters for gaming and fast typing, where simultaneous inputs must not be missed or ghosted.
Why does my keyboard stop registering after a few keys?
Most standard keyboards use a matrix circuit with limited rollover, often 2 or 6 keys. When you exceed that limit, additional presses may be ignored. This test helps you see that behavior, not change it.
Does this test work with wireless keyboards or laptops?
Yes, it works with any keyboard connected to your device. However, wireless connections or internal laptop keyboards may have lower rollover limits or added latency, which the test will naturally reflect.