Date of birth needs to be earlier than the Today's date.
How to calculate my age
To calculate age based on date of birth, enter or select your date of birth in the first box. Click on 'Calculate' to get the age in years, months and days
To find the age difference or age on a future date or past date, change the 'age at the date of' to another date.
By default, it shows the current date to find the age.
Age Calculator from dob formula
Formula for Age calculator in years (age difference calculator).
time difference = todays date time- date of birth time.
year = time difference/ (24 * 60 * 60 * 1000) / 365.25.
Formula for Age calculator in months.
months = (todays date year - date of birth year) * 12 + (todays date month - date of birth month).