Everyone who has ever been born, standing in one line in the order they arrived. There are about 117 billion of them. Here is exactly where you are standing.
Nothing is sent anywhere. The date stays in your browser and is only used to work out the arithmetic below.
Two sources, joined at 1950. The Population Reference Bureau's How Many People Have Ever Lived on Earth? (2022) estimates that 107,901,175,171 people had been born by 1950, working back through prehistory from assumed birth rates. From 1950 onward this page adds up the UN World Population Prospects 2024 annual birth figures, year by year, and splits each year evenly across its days.
The join is the part worth checking, so here is the check: run the UN births forward from the Bureau's 1950 anchor and you reach 117.07 billion by 2022, against the Bureau's own published 117.02 billion. The two agree to 0.04%. Before 1950 the page interpolates between the Bureau's benchmarks, so a date in the 1930s is much rougher than one in the 1990s.
None of this is precise to the person, and it cannot be. The deep past is an estimate built on estimated birth rates, and the honest reading of your number is its first two or three digits. What it is good for is the shape: how much of humanity came before you, and how very recently almost none of it did.
Counts of people ever born from the Population Reference Bureau,
2022. Births, deaths and population from the UN World Population Prospects 2024,
via Our World in Data.
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