Mouse Sensitivity and You

An interactive journey in the land of half-truths

What is mouse DPI (CPI)? Dots per inch (DPI) is the number of pixels in one inch (2.54cm.) Mouse DPI, properly known as counts per inch (CPI) and formerly known as polls per inch (PPI), is the number of times your mouse notifies the computer of its position per inch moved. If you had 4 CPI your mouse would tell the computer it moved four times for every inch it traveled.

Does high CPI increase accuracy? No. There is no relationship between mouse CPI and accuracy. CPI relates directly to how sensitive a mouse is when moved. At a true 400 CPI your mouse will cover 400 pixels per inch which translates to the entire length of a 1280x1024 screen in 3.2 inches. At 800 CPI that same screen would take 1.6 inches of mouse movement.

What is adjustable CPI good for? It's excellent for obtaining the perfect mouse sensitivity in applications that don't allow you to numerically adjust your mouse sensitivity.

Is lower or higher windows sensitivity bad? Going over 6/11 in windows sensitivity will result in skipped pixels. At 7/11 one pixel is occasionally skipped, and at higher sensitivities the minimum mouse movement becomes multiple pixels. At lower windows sensitivities certain amounts of movement are thrown out, but minimal mouse movement results in 1 pixel of movement still.

What about usb poll rate? Changing your usb poll rate from 125hz to 500-1000hz does make the mouse slightly more responsive. It has no effect on sensitivity settings, but it changes the polling interval from 8ms to 2ms (500hz) or 1ms (1000hz). Most gamers want to run games at 100 fps (10ms per frame displayed) or 60 fps (16.67ms per frame) depending on the genre. This means that changing your usb poll rate could potentially make your mouse inputs display up to 1 frame faster.

What about monitor refresh rate? Monitor refresh rate has no effect on your sensitivity. It makes the mouse feel more responsive because the screen updates quicker.

How does screen resolution factor in? It depends on the application. In nearly all fps games your mouse sensitivity stays the same when you change resolutions. In the windows desktop and most other genres of games your mouse has a larger pixel distance to travel when you increase the resolution.

What is the best way to adjust mouse sensitivity? Your windows sensitivity should be 6/11. From there sensitivity should be adjusted in-game or through mouse dpi/cpi settings. If you have a mouse without adjustable dpi/cpi you can also lower windows sensitivity if you don't have enough control in-game and the mouse remains too sensitive.

.Windows SensitivityMouse DPI (CPI)Game SensitivityVirtual CPIDistance per Pixel

Version 4 - August 12th, 2010