What this test measures
The test takes the moment your system recorded the press and waits until the browser has drawn the frame that shows it. That covers your system, the browser and the refresh rate of your screen. It does not include the delay inside the mouse, keyboard or controller before the signal reaches the computer, or the time the monitor takes to light up the new frame, because no website can see those.
Use it to compare: a wired versus wireless mouse, Bluetooth versus USB for a controller, or game mode on and off on a TV that you use as a PC monitor. Take at least 20 samples and compare the averages.
Typical results
| Screen refresh | Expected average here |
|---|---|
| 60 Hz | About 17 to 35 ms |
| 144 Hz | About 7 to 15 ms |
| 240 Hz | About 4 to 10 ms |
Much higher numbers point to a busy computer, power saving, or a browser that is limiting frames. See the refresh rate test.
How to lower input lag
- Use a high refresh monitor and make sure it is set to its top rate.
- Use wired or 2.4 GHz wireless with a receiver instead of Bluetooth for mice and controllers.
- On a TV, turn on Game mode. It can cut more than 50 ms.
- Raise the mouse polling rate to 1000 Hz.
- Close heavy background apps.
Frequently asked questions
Short answers to the questions people ask most about this test.
What is input lag?
Input lag is the delay between pressing a button and seeing the result on screen. It adds up from the device, the computer, the software and the display.
Can a website measure my monitor input lag?
Not fully. A website cannot see when the monitor actually lights up a frame. Measuring true display lag needs a camera or a light sensor.
Is Bluetooth slower than wired?
Usually yes, by a few milliseconds, and it varies more. Run this test with both connections to compare.