Level Guide (median-based)
What Is Keyboard Input Latency?
The small delay between pressing a key and seeing its effect on screen. Invisible in everyday writing, but tangible in competitive and rhythm games.
The keyboard alone doesn't determine it: connection type, system load, and display timing stack into the total delay you actually feel.
How to Read the Numbers
Measurements vary, so anchor on the median rather than the average — it won't be dragged by the one run that happened to hitch.
Check jitter too: the spread of the values, where smaller means steadier. Consistent response matters more to game feel than the raw number itself.
How to Reduce Input Lag
- Use a wired connection — wireless varies widely between products
- Use a higher refresh rate display to shorten time-to-screen
- Measure with IME (e.g. Japanese input) off; conversion processing adds time
- Audit resident software — key-monitoring utilities can slow input
- Plug directly into the PC, not through a USB hub
This test measures in-browser processing time, not the keyboard hardware in isolation. Use it for comparisons across setting changes in the same environment.
What Is Keyboard Input Latency?
Input latency is the processing delay from a key press until the browser renders the next frame. The smaller the value, the faster your input reaches the screen.
This tool measures the gap between the moment a key press is detected and the next render timing, reported as input-to-render latency.
What Affects the Results
Browser JS load, refresh rate (Hz), VSync, OS input processing, and your keyboard’s polling rate all combine to shape the number. Even in the same setup, tab load shifts the values — close other tabs before measuring.
Tips for Stable Measurement
Press keys at a steady rhythm and avoid any other activity during the run. Background tabs and heavy processes push the values up. Base your judgment on the median.