Age Calculator
Exact age in years, months and days, plus next birthday. Runs in your browser.
About this age calculator
This age calculator tells you exactly how old you are in years, months and days. Enter a date of birth and it works out your age today, or on any other date you choose. You also see the day of the week you were born, your age in total months, weeks, days and hours, and how many days are left until your next birthday.
It suits anyone who needs a precise age rather than a rough one: parents counting a baby's age in months, people filling in forms with an age cut-off, and anyone who simply wants to know how many days they have been alive.
The math uses plain calendar dates, not clock times, so your result can't shift by a day because of time zones or daylight saving time. Everything runs in your browser, and the dates you enter never leave your device.
Features
Exact years, months and days
Full calendar months are counted first, then the remaining days, which is how people normally state an age.
Age on any date
The "age on" date starts at today. Change it to see how old someone was or will be on a past or future date, such as an exam or enrollment deadline.
Totals in months, weeks, days and hours
See your age as total months, whole weeks plus leftover days, total days and approximate hours.
Weekday of birth
Find out whether you were born on a Monday or a Saturday, for any date from year 1 to 9999.
Next birthday countdown
See how many days remain until your next birthday, which weekday it falls on, and the age you will turn.
Clear Feb 29 rule
If you were born on February 29, your birthday in common years is counted as February 28, and the tool says so.
Live results, no time zone errors
Results update as you type. Calendar math uses whole dates, so your location and daylight saving changes can't move the answer.
How to use the age calculator
- 1Enter your date of birth.
- 2Optionally change the 'age on' date.
- 3Read your exact age.
When to use it
Forms and applications
Check your exact age for a passport, visa, insurance or job application that asks for years and months.
Age cut-offs
Set the "age on" date to a school start date, a sports registration deadline or a retirement date to see whether someone qualifies.
Baby and child milestones
Doctors and parents often track young children in months or weeks. The totals give you both at a glance.
Birthday planning
See how many days are left until a birthday and which day of the week it falls on.
Fun facts
Find out how many days or hours you have been alive, or the weekday you were born.
How age is calculated (and why months are tricky)
Years and days are easy. Months are not, because they have 28, 29, 30 or 31 days. To keep results consistent, this calculator counts how many whole months fit between the two dates, then counts the days that are left over.
A whole month runs from one date to the same date in the next month, such as March 10 to April 10. When the next month is too short to contain that date, the month ends on its last day instead. That means January 31 plus one month is February 28, or February 29 in a leap year.
- January 31 to February 28, 2023: 1 month, 0 days.
- January 31 to March 1, 2023: 1 month, 1 day.
- February 28 to March 31, 2022: 1 month, 3 days.
- May 15, 1990 to October 30, 2026: 36 years, 5 months, 15 days.
Leap years and February 29 birthdays
A leap year has 366 days, with an extra day on February 29. A year is a leap year when it divides by 4, except century years, which must divide by 400. So 2000 was a leap year, but 1900 was not.
People born on February 29 only see their real birthday once every four years. This calculator treats February 28 as the birthday in common years, so someone born on February 29, 2000 turns 1 on February 28, 2001. Some countries use March 1 for legal purposes, so check local rules if the date matters for a contract or a license.
Why some age calculators are off by a day
Many web tools convert dates into clock times. If a date is read as midnight in one time zone and compared in another, or if a daylight saving change falls between the two dates, the difference can come out one day short or one day long.
This tool never uses clock times for the calculation. It reads each date as a plain year, month and day and counts days with a standard calendar formula. Today's date comes from your device's own calendar, so it matches the date you see on your screen.
Why use Mavros
| Mavros | Typical upload sites | |
|---|---|---|
| Results | Update instantly as you type | Need a Calculate button and a page reload |
| Time zone and daylight saving | Plain calendar math, no off-by-one days | Clock-based math that can drift by a day |
| Month-end rule | Explained on the page | Not explained |
| Feb 29 birthdays | Counted on Feb 28 and labeled | Often unclear |
| Ads | None in the way of the result | Ads around and between results |
| Privacy | Dates stay in your browser | Form data may be sent to a server |
Tips
- Use the "age on" date to check eligibility on a deadline, not just today's age.
- Press Today to reset the "age on" date after trying other dates.
- Hours are whole days times 24. For an exact count you would also need your time of birth.
- If you get an error, check the year. A birth date after the "age on" date isn't allowed.
- For a baby, read the total months and the weeks tile together for the usual milestone numbers.
Questions
How do I calculate my exact age?
Enter your date of birth. The calculator counts the whole years and months since that date, then the days left over, and shows the result immediately.
How old am I in days?
Your total age in days appears in the totals section under the main result, along with total months, weeks and approximate hours.
How do you count months when they have different lengths?
A month runs from one date to the same date in the next month. If the next month is too short, it ends on that month's last day, so January 31 plus one month is February 28 or 29. Any remaining days are counted separately.
How are February 29 birthdays handled?
In years without a February 29, the birthday is counted as February 28. The next birthday line tells you when this applies.
Can I find my age on a specific date?
Yes. Change the "age on" date to any past or future date. This is useful for school entry, sports or retirement cut-offs.
What day of the week was I born?
The result card shows the weekday of your birth date. For example, January 1, 2000 was a Saturday.
Why might another calculator give a result one day different?
Tools that use clock times can be thrown off by time zones or daylight saving changes. This one counts whole calendar dates, so its result doesn't depend on where you are.
Does it count the time of day I was born?
No. It works with dates only. The hours total is total days times 24, so treat it as an approximation.
Are my dates stored or sent anywhere?
No. The calculation runs in your browser and nothing you enter is sent to a server.