In demographics, the world population is the total number of humans currently living. As of March 2016, it was estimated at 7.4 billion, an all-time record high.[1] The United Nations estimates it will further increase to 11.2 billion in the year 2100.[1]

World population has experienced continuous growth since the end of the Great Famine of 1315–17 and the Black Death in 1350, when it was near 370 million.[2] The highest population growth rates – global population increases above 1.8% per year – occurred briefly during the 1950s, and for longer during the 1960s and 1970s. The global growth rate peaked at 2.2% in 1963, and has declined to 1.1% as of 2012.[3] Total annual births were highest in the late 1980s at about 139 million,[4] and are now expected to remain essentially constant at their 2011 level of 135 million,[5] while deaths number 56 million per year and are expected to increase to 80 million per year by 2040.[6] World population reached 7 billion on October 31, 2011 according to the United Nations Population Fund,[7][8][9] and on March 12, 2012 according to the United States Census Bureau.[10]

The median age of the world’s population was estimated to be 29.9 years in 2015. [11]

The 2012 UN projections show a continued increase in population in the near future with a steady decline in population growth rate; the global population is expected to reach between 8.3 and 10.9 billion by 2050.[12][13] 2003 UN Population Division population projections for the year 2150 range between 3.2 and 24.8 billion.[14] One of many independent mathematical models supports the lower estimate,[15] while a 2014 estimate forecasts between 9.3 and 12.6 billion in 2100, and continued growth thereafter.[16][17] Some analysts have questioned the sustainability of further world population growth, highlighting the growing pressures on the environment, global food supplies, and energy resources.[18][19][20]

Estimates on the total number of humans who have ever lived range in the order of 106 to 108 billion.[21][22][23][24]