What size 3-ring binder do I need?

As a rough rule of thumb cited across retailer listings: a 1" binder holds around 175–200 sheets, a 1.5" holds about 350, a 2" holds roughly 500–530, and a 3" can hold 600–670 sheets. For 800+ pages or bulky sheet protectors, step up to a 4"–6" capacity binder.