Exact model
A shared birthday in a room of 60
- Probability:
- 99.412%
- Odds:
- 169 to 1
- dBan
- +22.3 dBan
Among 60 people, more than 99 in 100 modelled groups contain a shared birthday.
Calculation
p = 1 − ∏ₖ₌₀⁵⁹ (365 − k) / 365 ≈ 0.99412266
Assumptions
Birthdays are independent and equally spread over 365 dates. Leap days are ignored.
Sources
- Uniform 365-day birthday model