Age Calculator
Exact age in years, months, and days from a date of birth.
Enter a date of birth to get an exact age in years, months, and days, plus the total number of days lived and the date of your next birthday.
How age is calculated
Your exact age is counted the same way you'd count it on a calendar:
- Whole years — how many birthdays have passed.
- Whole months since your last birthday.
- Remaining days since that month-day, using the real length of each month.
Because it uses actual calendar dates, February, 30-day months and leap years are all handled correctly instead of assuming every month or year is the same length.
Worked example
Someone born on March 15, 1990 is, on October 21, 2026:
- 36 years, 7 months and 6 days old
- 13,369 days old in total
- 145 days away from their next birthday on March 15, 2027
Common reasons to calculate an exact age
- Eligibility checks — school enrollment cut-off dates, sports age groups, or minimum ages for licenses and programs.
- Forms and records — set the "as of" date to the date on an application to see the age you were on that day.
- Milestones — find out when you'll be 10,000 or 20,000 days old, or how long until a big birthday.
Leap-year birthdays
People born on February 29 only see their exact birthday once every four years. For the countdown to the next birthday, this calculator uses March 1 in the years without a February 29, while your age in years, months and days is still counted from your real date of birth.
Frequently asked questions
Does this account for leap years?
Yes — the calculation is calendar-aware, using actual month lengths (including February in leap years), not a fixed 365-day average.
Can I calculate age as of a specific date, not today?
Yes — change the "as of" date to any date to see the age on that day, useful for eligibility checks or historical records.
How is my age in days calculated?
It counts every calendar day from your date of birth up to the "as of" date, including the extra day in each leap year along the way.
What if I was born on February 29?
In years without a February 29, this calculator treats March 1 as your birthday for the "next birthday" countdown. Laws and customs differ — some places use February 28 instead — so check if it matters for something official.
Why does my age in months and days sometimes look off by one?
Months have different lengths, so "one month" isn't a fixed number of days. The calculator counts whole months first and then the leftover days, borrowing the length of the month just before the "as of" date when it needs to — the same way you would count it on a calendar.