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How many people were born at the same hour as me?

A wonderful dilemma, isn't it?

I recently wondered how many people were born on the same day, at the same hour, and the same second as me. Another question is how many should be born in a hospital at the same time; that's a different problem, but we can get to that later.

Of course, someone has already done these calculations, but I did them in my head without looking anywhere, so now I'll share my method with you.


A very interesting topic, as usual - and since I know how to use my calculator, it helps with the calculations.


  • Number of people: 40 million
  • Distribution of births: linear (utter nonsense)
  • Average lifespan: 65 years = 569,400 hours


Since there are 40 million people, each of them is in one of those ~600k hours of life. Assuming they are linearly distributed in those hours, dividing 40 million by ~600k will tell us how many people are born in one hour. The result is approximately 70.

About 70 people were born at the same hour as me, which means roughly 1.17 people in the same minute, and 0.02 in the same second.

0.02 = 2%, which means a 2% probability that someone was born in the same second.

Of course, I'm talking about Poland.

I experienced this myself - that there are many people born at the same time. At one point, I clicked on a link on a forum to see people born on the same day, and there were quite a few.

Calculation Errors

It's important to remember that a linear distribution doesn't exist. There are demographic peaks and valleys. Various events can cause a localized increase in the number of births, and even the time of day can influence it. However, the statistics themselves can be thought-provoking.


I wonder if I'll ever meet someone born on the same day at the same hour?

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