Get person's age in Ruby

Question

I\'d like to get a person\'s age from its birthday. now - birthday / 365 doesn\'t work, because some years have 366 days. I came up with the following code:

Answer 1

The answers so far are kinda weird. Your original attempt was pretty close to the right way to do this:

birthday = DateTime.new(1900, 1, 1)
age = (DateTime.now - birthday) / 365.25 # or (1.year / 1.day)

You will get a fractional result, so feel free to convert the result to an integer with to_i. This is a better solution because it correctly treats the date difference as a time period measured in days (or seconds in the case of the related Time class) since the event. Then a simple division by the number of days in a year gives you the age. When calculating age in years this way, as long as you retain the original DOB value, no allowance needs to be made for leap years.