Use the slider to adjust your scrolling speed.Select Pointer Control from the menu on the left.

Go to System Preferences > Accessibility. To change your trackpad’s scrolling speed: You can do this a little at a time - as the speed changes immediately, you can test out different speeds on a document or web page. Use the slider to adjust your scrolling speed. This process is slightly different for a trackpad and a mouse. If you find yourself scrolling past important passages too quickly or inching down a page with long, sweeping scrolls, you might need to change your scrolling speed. This will reverse your scroll direction, regardless of whether it was already checked or not. To change the scroll direction of your mouse or trackpad, check (or uncheck) the box marked Scroll direction: Natural. If you’re using an external mouse, select Mouse. If you’re using your laptop’s trackpad, select Trackpad. Open System Preferences from the Apple menu. Is your Mac’s mouse wheel scrolling the wrong way? It’s no problem - you can easily change this from System Preferences. Mac Help Desk Mac tips How to change the scroll direction on Mac?

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