# 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] 2017/12/05 06:36 Female / 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] 2009/07/30 02:00 Male / More than 60 / Others / Very /

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