In any case, life was short. Life expectancy at birth probably averaged only about 10 years for most of human history. Average life expectancy in Iron Age France (from 800 B.C.E. to about 100 C.E.) has been estimated at only 10 or 12 years. Under these conditions, the birth rate would have to be about 80 live births per 1,000 people just for the species to survive. To put that in perspective, a high birth rate today is about 35 to 45 live births per 1,000 population, and it is observed in only some sub-Saharan African countries.
These short life expectancies mean that the human population had a hard time increasing. One estimate of the population of the Roman Empire, spanning Spain to Asia Minor, in 14 C.E. is 45 million. Other historians, however, set the figure twice as high, suggesting how imprecise population estimates of early historical periods can be.
By 1650, the world’s population rose to about 500 million—not a large increase from the estimate of 300 million in 1 C.E. The average annual rate of growth was actually lower in this period than the rate suggested for 8000 B.C.E. to 1 C.E. One reason for the unusually slower growth was the Black Death. This dreaded plague was not limited to 14th-century Europe but may have begun in western Asia in about 542 C.E. and spread from there. Experts believe that half the Byzantine Empire was destroyed by plague in the sixth century, a total of 100 million deaths. Such large fluctuations in population size over long periods greatly compound the difficulty of estimating the number of people who have ever lived.
By 1800, however, the world population passed the 1 billion mark and has since continued to grow to its current 8 billion (our most recent estimate as of 2022). This growth is driven in large part by advances in public health, medicine, and nutrition that have lowered death rates, allowing more people to live far into their reproductive years.
Assumptions Help Us Estimate Human Population History
Guesstimating the number of people ever born requires determining population sizes for different points in human prehistory and history and applying assumed birth rates to each period. We start at the very, very beginning—with just two people (a minimalist approach!). Although it is unlikely that humans descended from two people, this approach simplifies our estimation.
One complicating factor is the pattern of population growth. Did it rise to some level and then fluctuate wildly in response to famines and changes in climate? Or did it grow at a constant rate? We cannot know the answers to these questions, although paleontologists have produced a variety of theories. For the purposes of this exercise, we assumed a constant growth rate applied to each period up to modern times. Birth rates were set at 80 per 1,000 population annually through 1 C.E. and at 60 per 1,000 from 2 C.E. to 1750. Rates then declined to below the 20s by the modern period (see Table 1).
This semi-scientific approach yields an estimate of about 117 billion births since the dawn of modern humankind. Clearly, the period 190,000 B.C.E. to 1 C.E. is key to our estimate but, unfortunately, little is known about that era’s population size. If we were to challenge our conclusion at all, it might be that our method underestimates the number of births to some degree. The assumption of constant rather than highly fluctuating population growth in the earlier period may underestimate the average population size at the time.
We Account for a Large Percentage of People Who Have Ever Lived
Given a current global population of about 8 billion, the estimated 117 billion total births means that those alive in 2022 represent nearly 7% of the total number of people who have ever lived (see Table 2). Because we have existed on Earth for approximately 200,000 years, that’s actually a fairly large percentage.
TABLE 2. Snapshot of Population History
| Estimated number of people ever born | 117,020,448,575 |
| World population in mid-2022 | 7,963,000,000 |
| Percentage of those ever born who are living in 2022 | 6.8 |
As new archaeological discoveries are made and analyzed using increasingly innovative methods, our understanding of human population history will likely expand further, allowing us to improve on this ever-intriguing proposition!
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FAQs
With this context and timeframe in mind, the demographers estimate that 109 billion people have lived and died over the course of 192,000 years. If we add the number of people alive today, we get 117 billion humans that have ever lived.
How many humans have ever existed in total? ›
Still, with some assumptions about population size throughout human history, we can get a rough idea of this number: About 117 billion members of our species have ever been born on Earth.
How many humans lived 10,000 years ago? ›
The journey of our kind on Earth, all in numbers! By 10,000 B.C., the world's population was around 1 million. 2,000 years later there were about 5 million people on Earth—the same number that live in Finland today. 200 million people were scattered around the earth by 1 A.D. 1 in every 200 lived in Rome.
Are there more people alive than have ever died? ›
Not even close. It is estimated that in the 50,000 years of human history, more than 100 billion (in the American sense of billion as a thousand million) human beings have been born. Most estimates run somewhat higher. There are fewer than 6.4 billion alive today.
How many humans are left alive? ›
World Population Clock: 8.1 Billion People (LIVE, 2024) - Worldometer.
What is 1% of the world population? ›
Approximately 70,000,000 is one percent of the world's population. To estimate the number of the resident population in a certain territory, governments conduct censuses. The term "population" is frequently used to describe the total number of people living in a certain location.
How much longer can humans exist on Earth? ›
But how long can humans last? Eventually humans will go extinct. According to the most wildly optimistic estimate, our species will last perhaps another billion years but end when the expanding envelope of the sun swells outward and heats the planet to a Venus-like state. But a billion years is a long time.
What will life be like in 3000? ›
In the year 3000, humans will exist in a world transformed by advanced technologies, AI, and robotics. They will possess enhanced physical and mental capabilities, coexisting and collaborating with intelligent machines.
How did humans get on Earth? ›
The exact origin of modern humans, hom*o sapiens, has long been a topic of debate. Modern humans originated in Africa within the past 200,000 years and evolved from the now extinct hom*o erectus. Human evolution is an active area of research and current evidence supports an 'out of Africa' migration theory.
What was the lowest human population ever? ›
Estimates of the size of these populations are a topic of paleoanthropology. A late human population bottleneck is postulated by some scholars at approximately 70,000 years ago, during the Toba catastrophe, when hom*o sapiens population may have dropped to as low as between 1,000 and 10,000 individuals.
On October 18, 2023, the International Union for the Scientific Study of Population (2023) broadcast a Yes-or-No debate on the statement: “The population of humans that can be supported sustainably on the planet at a reasonable standard of living is below 4 billion.” Here is an abridged version of Joel E.
How many humans have died totally? ›
As of 2022, an estimated total of 109 billion humans have died, or roughly 93.8% of all humans to ever live. A substudy of gerontology known as biogerontology seeks to eliminate death by natural aging in humans, often through the application of natural processes found in certain organisms.
Is there more birth than death? ›
Natural increase plunged by nearly 79% to just 144,013 in 2021, indicating there were only 144,013 more births than deaths that year.
Will humans eventually go extinct? ›
Risk estimates. Given the limitations of ordinary observation and modeling, expert elicitation is frequently used instead to obtain probability estimates. Humanity has a 95% probability of being extinct in 7,800,000 years, according to J.
When did humans almost go extinct? ›
Modern humans—aka hom*o sapiens—emerged about 300,000 years ago after evolving from human ancestors. There's a lot we still don't know about who these ancestors were and where they lived. But according to an August 2023 study, our ancestors may have come close to extinction some 900,000 to 800,000 years ago.
When was the first human born? ›
Scientists still don't know exactly when or how the first humans evolved, but they've identified a few of the oldest ones. One of the earliest known humans is hom*o habilis, or “handy man,” who lived about 2.4 million to 1.4 million years ago in Eastern and Southern Africa.
Did humans exist 500000 years ago? ›
sapiens out of archaic human varieties derived from H. erectus, is estimated as having taken place over 500,000 years ago (marking the split of the H. sapiens lineage from ancestors shared with other known archaic hominins).
Have humans existed for 200000 years? ›
Modern humans evolved in Africa around 200,000 years ago. They have a higher and more rounded brain case, smaller faces and brow ridges, and a more prominent chin than other ancient humans.
How many humans will ever exist? ›
Depending on the projection of the world population in the forthcoming centuries, estimates may vary, but the argument states that it is unlikely that more than 1.2 trillion humans will ever live.
How many human species were there in total? ›
We hom*o sapiens didn't used to be alone. Long ago, there was a lot more human diversity; hom*o sapiens lived alongside an estimated eight now-extinct species of human about 300,000 years ago.
