Same birthday probability Calculator
Calculates the probability that one or more pairs in a group have the same birthday. | ||
(1) the probability that all birthdays of n persons are different. (2) the probability that one or more pairs have the same birthday. This calculation ignores the existence of leap years. |
Related links |
Birthday problem (wikipedia) |
Same birthday probability
[1-2] /2 | Disp-Num | ![]() ![]() |
- Purpose of use
- Settling an argument.
- Comment/Request
- In a random sample of "n" people, 2 are found to share the same birthday.
In a second random sample of people, 2 are found to share the same birthday.
What are the odds that both pairs of people share the same birthday?
[1] 2017/12/04 21:36 40 years old level / Others / A little /
- Purpose of use
- Very useful for backing up a bet taken in a pub. Thank you - I won.
- Comment/Request
- I love this kind of "dispute" settler - in addition, the formulae are beautifully complex in appearance, so my non-maths friends are entirely bamboozled.
[2] 2009/07/29 17:00 More than 60 / Others / Very /


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