Hey there! As a fellow Windows user, let's walk through your keyboard latency questions clearly and practically.

现有测试数据的准确性分析 #

First off, let's unpack those numbers from the Keyboard Latency Test tool:

• The 26ms shortest key press and 38.46Hz scan rate for your PS/2 keyboard actually line up with the protocol's typical behavior—PS/2 uses polling, and that scan rate is standard for many older PS/2 keyboards. That low minimum latency makes sense since PS/2 has less overhead than USB in some scenarios.
• Those extreme values (1204ms for Ctrl, 946ms for divide) are almost definitely outliers. They're probably caused by system background processes hogging resources when you pressed those keys, or even inconsistent pressure/timing on your part during testing. The fact that most presses were over 100ms also feels off—PS/2 keyboards usually have average latency way lower than that. So don't put too much stock in those extreme highs.

For your USB keyboard once it's dry: the same test should work in theory, but keep in mind USB keyboards have variable polling rates (common ones are 125Hz, 250Hz, 500Hz, 1000Hz). A 1000Hz USB keyboard will have average latency around 1ms, but the test might show slightly higher numbers due to OS processing delays.

更可靠的Windows延迟测试工具与方法 #

If you want more consistent, trustworthy results, here are some better options to try:

• Offline web-based keyboard tester: There's a well-known web tool you can save to your local drive and run without internet. It gives visual feedback and calculates average latency across multiple key presses, which is way more useful than just single extreme values.
• LatencyMon: This is a Windows-exclusive tool that monitors system-wide latency, including input devices. It can show you exactly how long your system takes to process keyboard input, helping you figure out if high latency is coming from the keyboard itself or background OS tasks. Just launch it while testing your keyboard and check the "Input Latency" section for insights.
• AutoHotkey custom script: You can whip up a simple script to measure key press latency directly. Here's a quick example:

  ~a::
      start := A_TickCount
      KeyWait, a
      end := A_TickCount
      ToolTip, Latency: % end - start % ms
      return
  

  Replace "a" with any key you want to test. This script shows you the exact time between pressing the key and the system registering it, right as a tooltip on your screen.

测试时的小技巧 #

• Close all unnecessary background apps (games, video editors, even heavy antivirus scans) to make sure your system isn't adding extra latency.
• Test each key multiple times and take the average—single high or low values don't tell the whole story.
• For USB keyboards: check if your model supports high polling rates (like 1000Hz) and make sure it's enabled via the keyboard's companion software or Windows device manager settings.

备注：内容来源于stack exchange，提问作者Idleavemypcwhenitdies