China has been the world's most populous country for a long time: back in 1750, it had a population of 225 million, around 28% of the world population.1 By 2016, China had a population larger than 1.4 billion.

But China is soon to be overtaken by India. In the chart below we see historic and projected population by country, spanning from 1800 through to 2100. The projections – made by the UN's Population Division – suggest that by 2024, India will surpass China to become the world's most populous country.

Projections are always associated with a degree of uncertainty and this means the crossing point could be a few years earlier or later. But even within this degree of uncertainty, it's expected that India will become the most populous country within the next decade.

Rapidly declining fertility rates – from an average of 6 children down to 2.4 children per woman – in India means its population growth has fallen significantly over the last few decades. This means that while it will be the most populous country for the rest of the century, it's expected to reach 'peak population' in the late 2050s at around 1.7 billion before slowly falling in the second half of the century.

Image: Our World in Data

What does the future population of other countries look like?

In the map below we see country populations across the world through to the year 2100. By clicking on any country you can see how its population has changed since 1950, and its projections over the 21st century.

Image: Our World in Data