This is a ranking of the cruise ships with the most passenger capacity. In this ranking, we consider the maximum passenger capacity, that is when all the rooms of the cruise ship are maximally occupied with passengers - in some cases, the maximum occupancy in a room can be more than two persons.

There is another accompanying term, double passenger capacity. You can find the figures for this term next to the maximum passenger capacity column in the table. Double passenger capacity refers to the case where all rooms are assumed to be normally occupied with two passengers.

Most of the numbers are based on figures reported in various Wikipedia pages.  So, it's as broad and useful a dataset as I can compile, attributed to Wikipedia. May you find something useful here.