Countries are ranked by population using estimates drawn from national censuses, birth and death records, surveys and demographic projections.
These figures help researchers compare countries, understand population growth and examine changes in global settlement patterns. However, rankings can vary depending on the data source and reference date.

It is also important to distinguish between population and population density. Population measures the number of residents, while density compares that number with land area.
The Campus Review provides an overview of country rankings, continental population patterns and density comparisons using 2026 estimates.
Read more:
https://thecampusreview.com/geography/countries-by-population/