How many babies are born worldwide each day?

How to get close to this number

Derive it from the population and a lifespan. If the world holds billions of people and each lives on the order of seventy years, then roughly a seventieth of the population is replaced every year, and dividing that by 365 gives the daily figure. This population-over-lifespan trick answers a surprising number of demographic questions without any demographic knowledge at all.

The mistake is treating births and population growth as the same thing. They are not: the world adds people because births outnumber deaths, and the explanation gives both figures. Falling birth rates can coexist with a growing population for decades, because the age structure of a population takes a generation to catch up with its fertility. That lag is the single most misunderstood idea in demography.

Where the births happen matters as much as how many. As the explanation notes, a quarter occur in one region and that share is expected to rise, which means the global figure is increasingly a statement about a few countries rather than about the world evenly. Projections like this come with scenario bands, and the figure quoted is the central case of one such projection.