At the dawn of agriculture, about 8000 B.C., the population of the world was approximately 5 million. Over the 8,000-year period up to 1 A.D., it grew to 200 million (some estimate 300 million or even 600, suggesting how imprecise population estimates of early historical periods can be), with a growth rate of under 0.05% per year.
A tremendous change occurred with the industrial revolution: whereas it had taken all of human history until around 1800 for world population to reach one billion, the second billion was achieved in only 130 years (1930), the third billion in 30 years (1960), the fourth billion in 15 years (1974), and the fifth billion in only 13 years (1987).
- During the 20th century alone, the population in the world has grown from 1.65 billion to 6 billion.
- In 1970, there were roughly half as many people in the world as there are now.
- Because of declining growth rates, it will now take over 200 years to double again.
Population in the world is currently (2018) growing at a rate of around 1.09% per year (down from 1.12% in 2017 and 1.14% in 2016). The current average population increase is estimated at 83 million people per year.
Annual growth rate reached its peak in the late 1960s when it was at around 2%. The rate of increase has nearly halved since then and will continue to decline in the coming years. It is estimated to reach 1% by 2023, less than 0.5% by 2052, and 0.25% in 2076 (a yearly addition of 27 million people to a population of 10.7 billion). In 2100, it should be only 0.09% or an addition of only 10 million people to a total population of 11.2 billion.
World population will, therefore, continue to grow in the 21st century, but at a much slower rate compared to the recent past. World population has doubled (100% increase) in 40 years from 1959 (3 billion) to 1999 (6 billion). It is now estimated that it will take another nearly 40 years to increase by another 50% to become 9 billion by 2037.
The latest world population projections indicate that world population will reach 10 billion persons in the year 2055 and 11 billion in the year 2088.
World Population Forecast (2020-2050)
- 2020: 7,795,482,309
- 2025: 8,185,613,757
- 2030: 8,551,198,644
- 2035: 8,892,701,940
- 2040: 9,210,337,004
- 2045: 9,504,209,572
- 2050: 9,771,822,753
World Population Milestones
10 Billion (2055)
The United Nations projects world population to reach 10 billion in the year 2056.
8 Billion (2023)
World population is expected to reach 8 billion people in 2023 according to the United Nations (in 2026 according to the U.S. Census Bureau).
7.6 Billion (2018)
The current world population is 7.6 billion as of April 2018  according to the most recent United Nations estimates elaborated by Worldometers. The term “World Population” refers to the human population (the total number of humans currently living) of the world.
7 Billion (2011)
According to the United Nations, world population reached 7 Billion on October 31, 2011.
The US Census Bureau made a lower estimate, for which the 7 billion mark was only reached on March 12, 2012.
6 Billion (1999)
According to the United Nations, the 6 billion figure was reached on October 12, 1999 (celebrated as the Day of 6 Billion). According to the U.S. Census Bureau instead, the six billion milestones was reached on July 22, 1999, at about 3:49 AM GMT. Yet, according to the U.S. Census web site, the date and time of when 6 billion was reached will probably change because the already uncertain estimates are constantly being updated.
- 5 Billion: 1987
- 4 Billion: 1974
- 3 Billion: 1960
- 2 Billion: 1930
- 1 Billion: 1804