What is measurable
Keydown and keyup timestamps, hold duration, and repeat intervals are available to the page. They reflect the full software path from OS to browser.
Keyboard Response Test
This test records the timing the browser can see: when keydown arrives, when keyup arrives, and how repeat events stream. It does not claim to measure physical switch latency.
Mobile note: Response measurement requires 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
Last hold Not measured
Repeat events 0
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
What is not measurable
A web page cannot see switch actuation, USB polling, or driver processing. Do not use this test as a hardware latency benchmark.
How to read a hold
A short clean hold shows one keydown and one keyup. A long hold adds repeat keydowns after the OS repeat delay, which is normal behavior.
Run a useful comparison
Press and release one ordinary letter, then repeat with a longer hold. The displayed interval is the time between browser keydown and keyup handling. It includes your hold and cannot isolate switch latency, USB polling delay or input-to-screen latency.
If the list stays empty, first verify a single ordinary letter. If a combination differs between attempts, record the operating system, browser, keyboard layout and connection, then change just one variable. A browser observes delivered events, not the keyboard matrix or firmware, so a missing event alone cannot identify the faulty component.
Browser event background: physical key codes and automatic repeat events. For a missing key, follow the step-by-step comparison procedure.
Related tools
Related guides
Is this a true latency test?
No. It measures browser-reported event timing, which includes OS and browser layers beyond the physical keyboard.
Why do repeat timings look irregular?
The OS repeat delay, system load, and browser timer resolution all affect the spacing between repeat events.
How do I interpret the key event timings shown here?
The timings show when your browser detected keyboard events, not physical switch actuation. Compare relative patterns, such as hold duration and inter-key gaps, to assess responsiveness consistency across keys or input methods.
Why do the event timestamps vary between browsers or devices?
Each browser and operating system reports timing at different polling or event-loop intervals. This tool measures those browser-reported timings, so variations across environments are expected. Use the same setup for consistent comparisons.
Can this test help me check if my keyboard is repeating characters too fast?
Yes. Watch the repeat stream interval—the time between repeated keydown events. Most systems maintain a fixed repeat delay and rate. Large fluctuations in that interval may indicate system load or keyboard firmware behavior.