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As of 22 January 2025, the human population of the world is estimated by the United States Census Bureau to be 8,155,300,000. The United Nations estimated the Earth's human population to be 6,800,000,000 in 2009. The world population has been growing continuously since the end of the Black Death around 1400.

The fastest rates of world population growth (increases above 1.8% per year) were seen briefly during the 1950s then for a longer period during the 1960s and 1970s (see graph). The 2008 rate of growth has almost halved since its peak of 2.2% per year, which was reached in 1963.

Annual births have levelled at about 134 million per year since their peak at 163 million in the late 1990s and are expected to remain constant. However, deaths are only around 57 million per year, and are expected to increase to 90 million by 2050. Because births outnumber deaths, the world's population is expected to reach 9 billion between 2040 and 2050.

The rapid increase in human population over the course of the 20th century has raised concerns about whether Earth is experiencing overpopulation. The scientific consensus is that the current population expansion and accompanying increase in usage of resources are linked to threats to the ecosystem, such as rising levels of atmospheric carbon dioxide, global warming, and pollution.

Population figures

A dramatic population bottleneck is theorized for the period around 70,000 BC (see Toba catastrophe theory). After this time and until the development of agriculture, it is estimated that the world population stabilized at about one million people whose subsistence entailed hunting and foraging, a lifestyle that by its nature ensured a low population density. It is estimated that more than 55 million people lived in the combined eastern and western Roman Empire (AD 300–400).

The Plague of Justinian caused Europe's population to drop by around 50% between 541 and the 700s. The population of Europe was more than 70 million in 1340. The Black Death pandemic in the 14th century may have reduced the world's population from an estimated 450 million to between 350 and 375 million in 1400. It took roughly 200 years for Europe's population to regain its 1340 level.

At the founding of the Ming dynasty in 1368, China's population was reported to be close to 60 million, and toward the end of the dynasty in 1644 it might have approached 150 million. England's population reached an estimated 5.6 million in 1650, up from an estimated 2.6 million in 1500. New crops that had come to Asia and Europe from the Americas via the Spanish colonizers in the 16th century contributed to the population growth. Since being introduced by Portuguese traders in the 16th century, maize and manioc have replaced traditional African crops as the continent’s most important staple food crops. Alfred W. Crosby speculated that increased production of maize, manioc, and other American crops "...enabled the slave traders drew many, perhaps most, of their cargoes from the rain forest areas, precisely those areas where American crops enabled heavier settlement than before."

The population of the Americas in 1500 may have been between 50 and 100 million. Encounters between European explorers and populations in the rest of the world often introduced local epidemics of extraordinary virulence. Archaeological evidence indicates that the death of around 90% of the Native American population of the New World was caused by Old World diseases such as smallpox, measles, and influenza. Over the centuries, the Europeans had developed high degrees of immunity to these diseases, while the indigenous peoples had no such immunity.

During the Agricultural and Industrial Revolutions, the life expectancy of children increased dramatically. The percentage of the children born in London who died before the age of five decreased from 74.5% in 1730-1749 to 31.8% in 1810-1829. Europe’s population doubled during the 18th century, from roughly one hundred million to almost two hundred million, and doubled again during the 19th century.

The population growth became more rapid after the introduction of compulsory vaccination and improvements in medicine and sanitation. As living conditions and health care improved during the 19th century, the United Kingdom's population doubled every fifty years. By 1801 the population of England had grown to 8.3 million, and by 1901 had grown to 30.5 million.

The population of the Indian subcontinent, which stood at about 125 million in 1750, had reached 389 million by 1941. Today, the region is home to 1.5 billion people. The total number of inhabitants of Java increased from about five million in 1815 to more than 130 million in the early 21st century. Mexico's population has grown from 13.6 million in 1900 to about 112 million in 2009. In eighty years, Kenya's population has grown from 2.9 million to thirty-seven million.

Population growth tables

Below is a table with historical and predicted population figures shown in millions.
The availability of historical population figures varies by region.

1. ^ Northern America comprises the northern countries and territories of North America: Canada, the United States, Greenland, Bermuda, and St. Pierre and Miquelon. Latin America comprises Middle America (Mexico, the nations of Central America, and the Caribbean) and South America.

The figures for North and Central America only refer to post-European contact settlers, and not native populations from before European settlement.

Rate of increase

Different regions have different rates of population growth. According to the above table, the growth in population of the different regions from 2000 to 2005 was:

237.771 million in Asia

92.293 million in Africa

38.052 million in Latin America

16.241 million in Northern America

3.264 million in Europe

1.955 million in Oceania

383.047 million in the whole world

In the 20th century, the world saw the biggest increase in its population in human history due to lessening of the mortality rate in many countries due to medical advances and massive increase in agricultural productivity attributed to the Green Revolution.

In 2000, the United Nations estimated that the world's population was growing at the rate of 1.14% (or about seventy-five million people) per year, down from a peak of eighty-eight million per year in 1989. In the last few centuries, the number of people living on Earth has increased many times over. By 2000, there were ten times as many people on Earth as there were three hundred years ago. According to data from the CIA's 2005–2006 World Factbooks, the world human population increased by an average of 203,800 people every day. The CIA Factbook increased this to 211,090 people every day in 2007, and again to 220,980 people every day in 2009.

Globally, the population growth rate has been steadily declining from its peak of 2.19% in 1963, but growth remains high in Latin America, the Middle East and Sub-Saharan Africa.

In some countries there is negative population growth (i.e. net decrease in population over time), especially in Central and Eastern Europe (mainly due to low fertility rates). Within the next decade, Japan and some countries in Western Europe are also expected to encounter negative population growth due to sub-replacement fertility rates.

In 2006, the United Nations stated that the rate of population growth is diminishing due to the demographic transition. If this trend continues, the rate of growth may diminish to zero, concurrent with a world population plateau of 9.2 billion, in 2050. However, this is only one of many estimates published by the UN. In 2009, UN projections for 2050 range from about 8 billion to 10.5 billion.

• Population (est.) 10,000 BC–AD 2000.
• Population (est.) 10,000 BC–AD 2000 in log y scale
• World population 1950–2000
• Increase rate 1950–2000

Models

Hoerner (1975) proposed the following formula:

${\displaystyle N={\frac {C}{T_{0}-T}}}$

where

• N is current population
• T is the current year
• C = 2·10
• T₀ = 2025

which represents hyperbolic growth with an infinite population in 2025.

According to Kapitsa (1997), the population grew between 67,000 BC and 1965, and the world population growth formula is:

${\displaystyle N={\frac {C}{\tau }}\operatorname {arccot} {\frac {T_{0}-T}{\tau }}}$

where

• N is current population
• T is the current year
• C = (1.86±0.01)·10
• T₀ = 2007±1
• ${\displaystyle \tau }$ = 42±1

The transition from hyperboles to slower rates of growth is related to the demographic transition.

Milestones

The population of the world reached one billion in 1804, two billion in 1927, three billion in 1960, four billion in 1974, five billion in 1987, and six billion in 1999. The population of the world is projected to reach seven billion in 2011 or 2012, eight billion in 2025, nine billion in 2040, and ten billion in 2061.

There is no estimation on the exact day or month the world's population surpassed both the one and two billion marks. The day of three and four billion were not officially celebrated, but the International Database of the United States Census Bureau places them in July 1959 and April 1974. The United Nations did determine, and celebrate, the "Day of 5 Billion" (11 July 1987), and the "Day of 6 Billion" (12 October 1999). The International Programs division of the United States Census Bureau estimated that the world reached six billion on 21 April 1999 (several months earlier than the official United Nations day). The "Day of 7 Billion" has been targeted by the United States Census Bureau to be in July 2012, while the Population Division of the United Nations suggests some time in late 2011.

Years for population to double

Using linear interpolation of the UNDESA estimates, the world population has been doubled or will double in the following years (with two different starting points). Note how, during the 2nd millennium, each doubling has taken roughly half as long as the previous doubling, fitting the hyperbolic growth model mentioned above. However, it is unlikely that there will be another doubling in the current century.

Distribution by region

Asia accounts for over 60% of the world population with almost 3.8 billion people. China and India together have about 40 percent of the world's population. Africa follows with 840 million people, 12% of the world's population. Europe's 710 million people make up 11% of the world's population. North America is home to 514 million (8%), South America to 371 million (5.3%), and Australia to 21 million (0.3%).

Most populous nations

The 16 countries with the largest total population:

Rank	Country / Territory	Population	Date	% of world population	Source
1	Peoples Republic of China	1,437,620,000	January 22, 2025	17.63%	Chinese Official Population Clock
2	India	1,407,080,000	January 22, 2025	17.25%	Indian Official Population Clock
3	United States	339,113,000	January 22, 2025	4.16%	United States Official Population Clock
4	Indonesia	231,369,500		2.84%	Statistics Indonesia
5	Brazil	218,558,000	January 22, 2025	2.69%	Brazilian Official Population Clock
6	Pakistan	Template:PakistanPopCommas	January 22, 2025	Expression error: Unrecognized punctuation character "[".%	Official Pakistani Population clock
7	Bangladesh	162,221,000	2009	1.99%	UN estimate
8	Nigeria	154,729,000		1.9%	UN estimate
9	Russia	141,927,297	January 1, 2010	1.74%	Federal State Statistics Service of Russia
10	Japan	127,530,000	December 1, 2009	1.56%	Official Japan Statistics Bureau
11	Mexico	107,550,697		1.32%	INEGI estimate National Population Statistics of Mexico
12	Philippines	92,226,600	Mid-2009	1.13%	National Statistics Office medium projection
13	Vietnam	85,789,573	April 1, 2009	1.05%	Preliminary 2009 census results
14	Germany	81,882,342	March 31, 2009	1%	Federal Statistical Office
15	Ethiopia	79,221,000	July 2008	0.97%	Ethiopia Central Statistics Agency
16	Egypt	101,048,000	January 22, 2025	1.24%	Official Egyptian Population clock

Approximately 4.54 billion people live in these sixteen countries, representing roughly two-thirds (66.7%) of the world's population as of February 2009.

Population density

The 10 most densely populated countries/regions

Rank	Country/Region	Population	Area (km)	Density (Pop per km)	Notes
1	Monaco	32,719	1.95	16,779
2	Singapore	4,620,657	707.1	6,535
3	Vatican City	824	0.44	1,873
4	Maldives	385,375	298	1,293
5	Malta	404,032	316	1,279
6	Bahrain	723,967	665	1,089
7	Bangladesh	157,813,124	147,570	1,069
8	Palestinian territories	4,223,760	6,020	702
9	Nauru	13,918	21	663
10	Taiwan	22,955,395	36,190	634

Countries ranking in the top both in terms of total population (more than 15 million people) and population density (more than 250 people per square kilometer):

Rank	Country	Population	Area (km)	Density (Pop. per km)	Notes
1	India	1,198,003,000	3,287,263	353	Growing country
2	Bangladesh	157,813,124	143,998	1,069	Fast growing country
3	Japan	127,170,110	377,873	337	Declining in population
4	Philippines	93,843,460	300,076	313	Fast growing country
5	Vietnam	85,789,573	331,689	259	Growing country
6	United Kingdom	62,041,708	243,610	255	Steady in population
7	South Korea	49,354,980	99,538	493	Steady in population
8	Taiwan	22,955,395	35,980	639	Steady in population
9	Sri Lanka	20,238,000	65,610	309	Slow growing country
10	Netherlands	16,608,975	41,526	400	Steady in population

Ethnicity

The world is made up of thousands of ethnic groups. The single largest ethnic group on the planet by far is Han Chinese, which represents 19.73% of the global population.

Demographics of youth

According to the 2006 CIA World Factbook, around 27% of the world's population is below 15 years of age.

Before adding mortality rates, the 1990s saw the greatest number of raw births worldwide, especially in the years after 1995, despite the fact that the birth rate was not as high as in the 1960s. In fact, because of the 163 million-per-year raw births after 1995, the time it took to reach the next 10 reached its fastest pace (only twelve years), as world population reached six billion people in 1999, when at the beginning of the decade, the reaching was designated for 2000, by most demographers.

1985–1990 marked the period with the fastest yearly population change in world history. Even though the early 1960s had a greater growth rate than in the mid and late 1980s, the population change hovered around eighty-three million people in the five-year period, with an all-time growth change of nearly eighty-eight million in 1990. The reason is that the world's population was greater in the mid- and late-1980s (around five billion) than in the early 1960s (around three billion), which meant that the growth rate in the 1980s was no factor on the dramatic population change.

Forecast

In the long run, the future population growth of the world is difficult to predict and the UN and US Census Bureau give different estimates. According to the latter, world population will hit seven billion in July 2012 or by late 2011, according to UN prediction.

Birth rates are declining slightly on average, but vary greatly between developed countries (where birth rates are often at or below replacement levels), developing countries, and different ethnicities. Death rates can change unexpectedly due to disease, wars and catastrophes, or advances in medicine.

The UN has issued multiple projections of future world population, based on different assumptions. Over the last ten years, the UN has consistently revised these projections downward, until the 2006 revision issued March 14, 2007 revised the 2050 mid-range estimate upwards by 273 million.

In some scenarios, disasters triggered by the growing population's demand for scarce resources will eventually lead to a sudden population crash, or even a Malthusian catastrophe (also see overpopulation and food security).

Predictions based on population growth

In 1798 Thomas Malthus incorrectly predicted that population growth would out-run food supply by the mid 19th century. In 1968, Paul R. Ehrlich reprised this argument in The Population Bomb, predicting famine in the 1970s and 1980s. The dire predictions of Ehrlich and other neo-Malthusians were vigorously challenged by a number of economists, notably Julian Lincoln Simon. Agricultural research already under way, such as the green revolution, led to dramatic improvements in crop yields. Food production has kept pace with population growth, but Malthusians point out the green revolution relies heavily on petroleum-based fertilizers, and that many crops have become so genetically uniform that a crop failure would be very widespread. Food prices in the early 21st century are rising sharply on a global scale, and causing serious malnutrition to spread widely.

From 1950 to 1984, as the Green Revolution transformed agriculture around the world, grain production increased by over 250%. The world population has grown by about four billion since the beginning of the Green Revolution and most believe that, without the Revolution, there would be greater famine and malnutrition than the UN presently documents (approximately 850 million people suffering from chronic malnutrition in 2005). The energy for the Green Revolution was provided by fossil fuels in the form of fertilizers (natural gas), pesticides (oil), and hydrocarbon-fueled irrigation.

The peaking of world oil production (Peak oil) may test Malthus and Ehrlich critics. As of May 2008, the price of grain has been pushed up by increased farming for use in biofuels, world oil prices at over $140 per barrel ($880/m), global population growth, climate change, loss of agricultural land to residential and industrial development, and growing consumer demand in China and India. Food riots have recently occurred in some countries across the world.. However, oil prices have fallen sharply since then, and they have remained below $100/barrel since September 2008. Resource demands are expected to ease as population growth declines, but it is unclear whether rising living standards in developing countries will once again create resource shortages.

Growing populations, falling energy sources and food shortages will create the "perfect storm" by 2030, the UK government chief scientist has warned. He said food reserves are at a fifty-year low but the world will require 50% more energy, food and water by 2030. The world will have to produce 70% more food by 2050 to feed a projected extra 2.3 billion people and as incomes rise, the United Nations' Food and Agriculture Organisation (FAO) said.

The observed figures for 2007 show an actual increase in absolute numbers of undernourished people in the world, 923 million in 2007 versus 832 million in 1995.; the more recent FAO estimates point out to an even more dramatic increase, to 1.02 billion in 2009.

Number of humans who have ever lived

Estimates of "the total number of people who have ever lived" published in the 2000s range approximately from 100 to 115 billion (1 E11).

An estimate of the total number of people who have ever lived was prepared by Carl Haub of the Population Reference Bureau in 1995 and subsequently updated in 2002; the updated figure was approximately 106 billion. Haub characterized this figure as an estimate that required "selecting population sizes for different points from antiquity to the present and applying assumed birth rates to each period". Given an estimated global population of 6.2 billion in 2002, it could be inferred that about 6% of all people who had ever existed were alive in 2002.

In the 1970s it was a popular belief that 75% of all the people who had ever lived were alive in the 1970s, which would have put the total number of people who ever lived as of the 1970s as less than the number of people alive today. This view was eventually debunked.

The number is difficult to estimate for the following reasons:

• The set of specific characteristics that define a human is a matter of definition, and it is open to debate which members of early Homo sapiens and earlier or related species of Homo to include. See in this regard also Sorites paradox. Even if the scientific community reached wide consensus regarding which characteristics distinguished human beings, it would be nearly impossible to pinpoint the time of their first appearance to even the nearest millennium because the fossil record is simply too sparse. However, the limited size of population in early times compared to its recent size makes this source of uncertainty of limited importance.
• Robust statistical data only exist for the last two or three centuries. Until the late 18th century, few governments had ever performed an accurate census. In many early attempts, such as Ancient Egypt and in the Persian Empire the focus was on counting merely a subset of the people for purposes of taxation or military service. All claims of population sizes preceding the 18th century are estimates, and thus the margin of error for the total number of humans who have ever lived should be in the billions, or even tens of billions of people.
• A critical item for the estimation is life expectancy. Using a figure of twenty years and the population estimates above, one can compute about fifty-eight billion. Using a figure of forty yields half of that. Life expectancy varies greatly when taking into account children who died within the first year of birth, a number very difficult to estimate for earlier times. Haub states that "life expectancy at birth probably averaged only about ten years for most of human history" His estimates for infant mortality suggest that around 40% of those who have ever lived did not survive beyond one year.

See also

Historical:

• Historical demography
• Classical demography
• Medieval demography
• The Day of Six Billion

Lists:

• List of religious populations
• List of countries by past and future population
• List of countries by population
• List of countries by population density
• List of countries by population growth rate
• List of countries by fertility rate

Further resources

• There is a map that is rescaled in order to display every country according to its population size. It is available at the University of Sheffield Worldmapper.
• Population patterns and trends can be explored on the GeoHive interactive world atlas.

References

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11. "Europe's Black Death is a history lesson in human tragedy — and economic renewal". TIME Europe. July 17, 2000, VOL. 156 NO. 3
12. Ming Dynasty. Microsoft Encarta Online Encyclopedia 2009.
13. "Qing China's Internal Crisis: Land Shortage, Famine, Rural Poverty". Asia for Educators, Columbia University.
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15. "China's Population: Readings and Maps". Columbia University, East Asian Curriculum Project.
16. The Columbian Exchange. The University of North Carolina.
17. Super-Sized Cassava Plants May Help Fight Hunger In Africa. The Ohio State University
18. "Albert Schweitzer: a biography". James Brabazon (2000). Syracuse University Press. p.242. ISBN 0815606753
19. "Savoring Africa in the New World by Robert L. Hall". Millersville University.
20. J. N. Hays (1998). "The burdens of disease: epidemics and human response in western history.". p 72. ISBN 0813525284
21. "The Story Of... Smallpox – and other Deadly Eurasian Germs". Public Broadcasting Service (PBS).
22. "Stacy Goodling, "Effects of European Diseases on the Inhabitants of the New World""
23. Population crises and cycles in history. A review of the book Population Crises and Population cycles by Claire Russell and W.M.S. Russell.
24. Mabel C. Buer, Health, Wealth and Population in the Early Days of the Industrial Revolution, London: George Routledge & Sons, 1926, page 30 ISBN 0-415-38218-1
25. BBC - History - The Foundling Hospital. Published: 2001-05-01.
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27. "United States People". Microsoft Encarta Online Encyclopedia 2009.
28. BBC - History - Victorian Medicine - From Fluke to Theory. Published: 2002-02-01.
29. "19th-Century Medicine". Microsoft Encarta Online Encyclopedia 2009.
30. A portrait of Britain in 2031. The Independent. October 24, 2007.
31. "The UK population: past, present and future" (PDF). Statistics.gov.uk. Retrieved 2009-09-05.
32. Reintegrating India with the World Economy. Peterson Institute for International Economics.
33. Hundreds of millions in South Asia face growing water stress, UN report warns. UN News Centre. February 6, 2009.
34. Java (island, Indonesia). Encyclopædia Britannica.
35. "From Traitors to Heroes: 100 Years of Mexican Migration Policies". Jorge Durand, University of Guadalajara. March 2004.
36. "Exploding population". The New York Times. January 7, 2008.
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38. The World at un.org
39. Population Growth over Human History
40. Geo Hive: the population of continents, regions and countries (Jul. 1, 2008)
41. UN report 2004 data
42. fewer than 15,000 individuals according to the Toba catastrophe theory; see also Humans lived in tiny, separate bands for 100,000 years (breitbart.com)
43. ^ an average of figures from different sources as listed at the US Census Bureau's Historical Estimates of World Population; see also *Kremer, Michael. 1993. "Population Growth and Technological Change: One Million B.C. to 1990," The Quarterly Journal of Economics 108(3): 681-716.
44. The range of figures from different sources as listed at the US Census Bureau's Historical Estimates of World Population put the population at AD 1 between 170 million to 400 million.
45. The limits of a Green Revolution?
46. The Real Green Revolution
47. World Population to 2300 Economic and Social Affairs, United Nations, 2004
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56. Letters to Nature: Doubling of world population unlikely Nature, 19 June 1997
57. Figure refers to Mainland China only. It excludes the special administrative regions and Taiwan.
58. For the Conapo estimates, check under Republica Mexicana and press "Ver" for statistics.
59. The Monaco government uses a smaller surface area figure resulting in a population density of 18,078 per km².
60. ^ Population density calculated using surface area and population figures from the CIA World Factbook.
61. mohammed al a'ali (April 1, 2008). Population surge 'threat to economy'. gulf Daily News. Retrieved 2008-04-21.
62. Latest figure from the World Bank Development Indicators Database is 1,090 per km².
63. Age structure of the world – 2006 CIA World Factbook
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68. Kindall, Henery W & Pimentel, David (1994). "Constraints on the Expansion of the Global Food Supply". Ambio. 23 (3). {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
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71. "Peak Oil: the threat to our food security". Soil Association.
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74. The global grain bubble
75. Food crisis will take hold before climate change, warns chief scientist
76. Global food crisis looms as climate change and fuel shortages bite
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78. Has Urbanization Caused a Loss to Agricultural Land?
79. The World's Growing Food-Price Crisis
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81. Riots and hunger feared as demand for grain sends food costs soaring
82. Already we have riots, hoarding, panic: the sign of things to come?
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91. Population Reference Bureau
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94. Global Statistics interactive atlas, GeoHive.

External links

• World Population Prospects, the 2008 Revision (United Nations Population Division).
• World population statistics presented in a treemap interface
• Year-by-Year World Population Estimates: 10,000 BC to AD 2007.
• Optimum Population Trust
• State of World Population 2007 report 27 June 2007 - United Nations Population Fund
• World Population Day United Nations: 11 July
• The Day of 6 Billion official homepage
• Trend of growth rate with total global population
• The World in Balance Transcript of two-part PBS' Nova on World Population
• BBC (1999). UN chief welcomes six billionth baby. URL accessed on March 7, 2005.
• Central Intelligence Agency (2004). CIA The World Factbook 2004. URL accessed on February 13, 2005.
• United Nations (2001). United Nations Population Information Network. URL accessed on February 13, 2005.
• United States Census Bureau (2004). Historical Estimates of World Population. URL accessed on February 13, 2005.
• PopulationData.net (2005). PopulationData.net - Information and maps about populations around the world.
• GeoHive GeoHive.com - World Statistics including population and future predictions.
• Population Reference Bureau www.prb.org - News and issues related to population.
• World maps, including maps of population from Year 1 to Year 2300
• Berlin Institute for Population and Development
• World Population from the US Census Bureau in an interactive Excel dashboard

Population clocks

• World Population Clock at the U.S. Census Bureau
• Population Counter
• World Population
• World Population Counter
• Live World Population
• Template:Fr icon World Population Clock (2005). WorldPopClock.com - World population clock.

• Population
• Demography
• Environmental science