Add the following function to a module in your database.
Public Function calcAge(dob As Date) As Integer Dim age As Integer age = DateDiff("yyyy", dob, Now()) calcAge = IIf(Format(dob, "mmdd") >= Format(Now(), "mmdd"), age - 1, age) End Function
You can call this function in a query just like a built in function. It takes the number of years between the data of birth and the current date. Then it adjusts it down 1 year if the birthday has not yet occurred for the current year.