In Page View, you can zoom in and out of your page or document with the Zoom In and Zoom Out controls
in the toolbar. You can also use trackpad gestures on your Mac.
Scale
You can zoom in or out using the Scale item in the toolbar. Click into the Scale field to change the percent manually. If the Scale item is not in your toolbar, add it by customizing your Toolbar.
Thumbnail Size
In the Sidebar, you can increase or decrease the size of the thumbnails with the slider
