mouse-sensitivity.com is described as 'Mouse Sensitivity Calculator and Converter - With this calculator you can calculate and convert sensitivity between over 200 games and over 400 aims! There are a lot of different conversion methods, but Viewspeed is the recommended method for most users' and is an website in the OS & Utilities category. There are four alternatives to mouse-sensitivity.com, not only websites but also apps for Windows. The best alternative is Aiming.Pro, which is free. Other great sites and apps similar to mouse-sensitivity.com are Elite Ownage's Sensitivity Calculator (Free), Sensitivity Matcher (Free, Open Source) and Mouse Sensitivity Calculator (Free).
Consistent mouse looking between games makes it so your body does not need to adjust when switching games. Consistent mouse aiming will improve your accuracy, reaction time, and confidence in every game you play.