Age Calculator

An age calculator gives the exact time between a date of birth and another date, expressed in complete years, months and days.

Counting an age by hand goes wrong on the awkward cases: months of different lengths, leap years, and birthdays that have not happened yet this year. This tool uses the calendar itself, so 29 February and the end of a short month are handled the way a registrar would handle them. It also answers the follow-up questions — age in months, weeks and days, the day of the week you were born, and when the next birthday falls.

1. Enter the date of birth.
2. Leave the second date as today, or change it to work out an age on another date.
3. Read the exact age, and the same age expressed in months, weeks and days.

years  = complete years between the dates
months = complete months after those years
days   = remaining days after those months

Each part is counted against the real calendar rather than against an average month, so the answer matches how ages are stated on official forms.

Someone born on 29 February 2004, on 16 September 2026.

2027 is not a leap year, so the birthday is observed on 1 March.

• A date of birth in the future has no answer, so the calculator asks you to correct the dates instead of showing a negative age.
• For a 29 February birthday in a common year, the next birthday is shown as 1 March, the usual civil convention in India and most other places.
• Ages are counted in whole days from midnight to midnight; the time of day is not used.