Age Calculator
Enter a date of birth to see the exact age in years, months and days, how many days that is, and how long until the next birthday. Change the second date to find an age on any other day.
–Age
- Pick two dates
Age is counted in whole birthdays: you are one year older on the day your birth date comes round again, not a little each day.
How the age is worked out
The calculator first counts complete years: how many birthdays have passed by the second date. It then counts complete months since the last birthday, and finally the days since the last month mark. Because months have 28 to 31 days, a month here means the same day number in the next month, the way people say a baby is three months old.
Next to that reading the card shows the total number of days lived and the days until the next birthday, together with the age that birthday brings. For a plain count of days or weeks between any two dates, the days between dates calculator page gives the same span in more units.
Month ends and leap-day birthdays
Dates near the end of a month need one rule. A month is complete when the same day number comes round again; if the next month is too short to have that day, the month completes on the 1st of the month after. Born on January 31, a baby is 0 months and 28 days old on February 28 and exactly one month and one day old on March 1.
People born on February 29 have a real birthday only in leap years. In the other years the calculator moves it to March 1, so the age goes up the day after February 28.
When an exact date matters
Laws and institutions can count age differently from everyday use. Check the rule that applies before you rely on a borderline result.
- Some places treat a leap-day birthday as February 28 in common years.
- Schools often use a cutoff date, so a child's age on that date counts, not on the first day of class.
- Insurance and pensions may use the age at the nearest birthday rather than the last one.
Days in each month
| Month | 2026 | 2027 |
|---|---|---|
| January | 31 | 31 |
| February | 28 | 28 |
| March | 31 | 31 |
| April | 30 | 30 |
| May | 31 | 31 |
| June | 30 | 30 |
| July | 31 | 31 |
| August | 31 | 31 |
| September | 30 | 30 |
| October | 31 | 31 |
| November | 30 | 30 |
| December | 31 | 31 |
| Days | 365 | 365 |
Leap years ahead: 2028, 2032, 2036, 2040, 2044, 2048
The Gregorian calendar adds a leap day in every year divisible by 4, except century years that are not divisible by 400. That is why 2000 was a leap year and 1900 was not, and why the average year is 365.2425 days long. The days between dates calculator uses the same rules.
Common reasons to check an exact age
- Forms and applications that ask for age on a given date, such as a visa or an exam.
- Eligibility limits for sports categories, school entry or age-restricted services.
- Milestones like 10,000 days old, which the total days figure shows directly.
- Planning a birthday: the card counts down the days to the next one.
Age calculator questions
How is age calculated in years, months and days?
Count the whole years since the birth date, then the whole months after the last birthday, then the days left over. Someone born on March 20, 2000 is 26 years, 7 months and 8 days old on October 28, 2026.
How old is someone born on February 29?
They gain a year every year like everyone else. In common years the calculator places the birthday on March 1, the day after February 28; some legal systems use February 28 instead, so check local rules when it matters.
Can I find someone's age on a past or future date?
Yes. Change the second date from today to any other day, for example the date of an exam, a contract or a retirement, and the age updates.
Does the time of birth matter?
Not for ages counted in years, months and days, which is how forms, schools and laws count age. The calculator works with dates only, in your device's time zone.
How many days old am I?
The card lists the total days lived next to the age. Leap days are included, so the total is a little more than 365 times the years.