Age Calculator
A precise age calculator: years, months and days lived, your age in total days, and a live countdown to the next birthday.
How to use
- Pick your date of birth in the first field.
- Optionally change the “as of” date to compute an age at another point in time.
- Read your exact age, total days lived, and the next-birthday countdown.
Frequently asked questions
How is the exact age in years, months and days computed?
Full periods are counted: your age in years increases on each birthday, then complete months after that, and the leftover days make up the rest. All date math runs in UTC so the result does not shift with time zones or daylight saving changes.
Why is the total days figure sometimes one day off from another site?
Most sites count the days between calendar dates (your first day alive is day 0 here). A handful count the birth day itself as day 1, which shows one extra day. Both conventions exist — this tool uses the day-0 convention consistently.
What happens if my birthday is on February 29?
Leap-day birthdays are celebrated on March 1 in common years, and that is what the countdown uses. Your age in years still increases on the anniversary, February 29 in leap years.
Can I calculate an age at a date in the past or future?
The “as of” date defaults to today and can be set to any other date — past or future — to answer questions like “how old was I on graduation day?” or “how old will I be in 2030?”. Ages for dates before the birth date show as invalid.
Is anything sent to a server?
No. The calculation happens entirely in your browser and your birth date is never stored or transmitted anywhere.