People's birthdays are taken one at a time at random. How many times can you do this before you find two people with the same birthday?
Months
January
February
March
April
May
June
July
August
September
October
November
December
Generate Birthdays
Birthdays: 0  Matches: 0
Minimum number of people
The minimum number of people for there to be a specific probability of two or more coincident birthdays
Probability:

Probability
The probability of two or more people sharing a birthday
Number of people:
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This question appears in the following syllabi:
Syllabus  Module  Section  Topic 

AQA ALevel (UK  Pre2017)  S1  Probability  Experimental 
AQA AS Maths 2017  Statistics  Probability  Experimental Probabilities 
AQA AS/A2 Maths 2017  Statistics  Probability  Experimental Probabilities 
CBSE XII (India)  Probability  Probability  Repeated independent (Bernoulli) trials and binomial distribution 
CBSE XI (India)  Statistics and Probability  Probability  Random experiments, outcomes, sample spaces (set representation) 
CCEA ALevel (NI)  S1  Probability  Experimental 
CIE ALevel (UK)  S1  Probability  Experimental 
M Statistics  Probability  M1 Mutually Exclusive and Independent  Experimental  
Edexcel ALevel (UK  Pre2017)  S1  Probability  Experimental 
Edexcel AS Maths 2017  Statistics  Probability  Experimental Probabilities 
Edexcel AS/A2 Maths 2017  Statistics  Probability  Experimental Probabilities 
I.B. Higher Level  5  Probability  Experimental 
I.B. Standard Level  5  Probability  Experimental 
Methods (UK)  M15  Probability  Experimental 
I.B. (MSSL)  3  Probability  Experimental 
OCR ALevel (UK  Pre2017)  S1  Probability  Experimental 
OCR AS Maths 2017  Statistics  Probability  Experimental Probabilities 
OCR MEI AS Maths 2017  Statistics  Probability  Experimental Probabilities 
OCRMEI ALevel (UK  Pre2017)  S1  Probability  Experimental 
PreCalculus (US)  E4  Probability  Experimental 
PreU ALevel (UK)  Prob  Probability  Experimental 
Scottish (Highers + Advanced)  HS  Probability  Experimental 
Scottish Highers  S  Probability  Experimental 
Universal (all site questions)  P  Probability  Experimental 
WJEC ALevel (Wales)  S1  Probability  Experimental 