100 people today. How many grandchildren?

Pick up to six countries and see how many children and grandchildren a group of people today would have if birth rates stayed where they are. Change any rate to see what a recovery — or a further fall — would do.

birthrate.ioFertility

100 people today. How many grandchildren?

2 generations at today's birth rates

Today
Children
Grandchildren

South Korea

births per woman

2025 · Provisional (national statistics)

100
38
15

Italy

births per woman

2025 · Provisional (national statistics)

100
54
29

Somalia

births per woman

2024 · World Bank

100
286
819
Source: TFR: Provisional (national statistics); World Bank. Each generation = previous × TFR ÷ 2.1. Ignores migration and timing.birthrate.io/grandchildren?c=korea-rep%2Citaly%2Csomalia-fed-rep&g=2&n=100

How it works: a total fertility rate (TFR) of 2.1 keeps a generation the same size, so each generation is the previous one × TFR ÷ 2.1. It assumes today's rate holds, and ignores migration, changing death rates and the age people have children. TFRs are the newest published value for each country from the fertility explorer; type any number to try another.