How to tell if you have mouse acceleration on
Go to your windows settings, mouse software, and in-game settings and check if it’s on. If you’re still not sure you should go into your game of choice and do this test:
determine a distance you’re going to move your mouse eg. from one side of your mousepad to the other
Slowly move your mouse the distance you chose while watching your in-game crosshair or cursor to see how far it goes
Now do the same thing again but move your mouse quickly across the same distance
If your crosshair or cursor moved the same distance each time then you don’t have mouse acceleration on. If you use a very high mouse sensitivity it may be harder to notice whether acceleration is on or not.