Though the world has 7.5 billion people in it already, most places are far from overcrowded. Look at these maps created by Max Galka. The yellow parts show areas where population density is more than 900 people per square mile. The black areas show areas with less than 900 people per square mile.
As you can see: there is a lot more black. In fact, all the yellow on the maps account more than half of the global population, despite being only 1% of the overall land space. Some places are very crowded, others not at all.
The biggest bursts of yellow are in India, Bangladesh, and China, which alone contain 46% of the global population, Galka says. Just the Chengdu/Chengking region, the big blob in the middle of China, holds 100 million people, even though most non-Chinese people have never heard of it.
The island of Java, in Indonesia, contains 140 million people, although it's only the size of New York State, Galka says. Europe, on the other hand, has well-spaced heavily populated areas. And North Africa has few yellow spaces (not a lot of population density in the Sahara). The exception is the Nile delta, where Cairo has one of the densest urban populations in the world.
Galka used data from NASA that divides the globe into three-by-three mile cells. There are 28 million cells in all. As for the United States, it follows the global pattern. Roughly half of Americans live in yellow bubbles and half in black areas.