Use the config file calculations for best range and accuracy.
Real Mouse DPI Analyzer
What is the real DPI of your mouse?
With this tool you can measure the real DPI of your mouse, and calculate the sensor accuracy. It can also be used to find out what your DPI actually is if you don't have a setting for it in your mouse driver. UPDATE!
You can now measure the X-axis both ways, select X- to measure from right to left.
The actual DPI is now shown with an accuracy of two decimals.
The target count and actually moved counts are also shown.
You need to accurately measure how far you move your mouse, so do something like drawing inch/cm lines on a piece of paper and use it as a mousepad.
Enter the target distance for how far you are moving your mouse.
Enter the current DPI setting, if known. You do not need to enter this, but it is necessary for the accuracy calculation.
Click the red crosshair, and hold the mousebutton down.
Move your mouse the target distance as mapped out on the piece of paper (or however you prefer to measure it).
Release the mousebutton to stop recording the movement.
Limitations and notes (IMPORTANT!)
All acceleration must be turned off, both in Windows (Control Panel\Hardware and Sound\Mouse\Pointer Options\Enhance pointer precision), and in the driver software. This is very important, if acceleration is on, the measurement is useless.
Your mouse pointer MUST stay within the confines of the monitor(s). If you hit the edge of your screen, the measurement will stop.
You do not have to stay within the browser window, you can drag the pointer outside as long as you do not hit the edge of the monitor.
If you are using multiple monitors, you can drag the pointer across them all.
When you drag the crosshair beyond the window border, the browser will start scrolling into emptyness, don't worry, it will reset when you release the button.
You do not have to start dragging the crosshair at the exact center, just click anywhere where the mouse pointer turns into a four-way arrow.