Age Calculator
Find your exact age in years, months and days from your date of birth, plus your next birthday, the days you have lived and the age difference between two people.
Based on the Gregorian calendar and the date on your device. For legal or official purposes, check the rules where you live.
Your dates
Your results
How to use the age calculator
Choose Age to find your exact age from a date of birth. The age date starts as today, so you can also find out how old you were on any past date or how old you will be on a future date. Choose Age difference to compare two dates of birth, for example you and a sibling or partner.
- Pick your date of birth.
- Leave “Age on this date” as today, or change it.
- Press Calculate to see your age in years, months and days, your next birthday and the days you have lived.
How age is calculated
Age is the number of complete years since birth, plus the complete months and days that have passed since your last birthday. The calculator counts years first, then months, then days. When the day count would be negative, it borrows the length of the previous month.
Example: born 15 June 1995, age on 19 October 2026. From 15 June 1995 to 15 June 2026 is 31 complete years. From 15 June 2026 to 19 October 2026 is 4 months and 4 days. The age is 31 years, 4 months, 4 days, which is 11,449 days in total.
Days, weeks, months and hours lived
| Age | Months | Weeks | Days | Hours |
|---|---|---|---|---|
| 1 year | 12 | 52 | 365 | 8,760 |
| 10 years | 120 | 521 | 3,652 | 87,658 |
| 18 years | 216 | 939 | 6,574 | 157,784 |
| 30 years | 360 | 1,565 | 10,957 | 262,975 |
| 50 years | 600 | 2,609 | 18,262 | 438,291 |
The table uses an average year of 365.2425 days, which includes leap years. Your exact total depends on your birth date, and the calculator above counts the real days between your two dates.
Day and second milestones
Many people like to know the date they turn 1,000 or 10,000 days old. At 10,000 days you are around 27 years and 4 to 5 months old. One billion seconds is 11,574 days, which is about 31 years and 8 months. The results above list the exact dates for your birth date.
Age systems around the world
Most countries use the international system, where your age goes up on your birthday. In the traditional Korean system, a baby is 1 at birth and gains a year every 1 January. South Korea moved to the international system for most legal and official uses in June 2023, but the traditional count is still known and used in daily life by some people. Other East Asian traditions also count age by calendar year or by lunar calendar. This calculator uses the international system and also shows the traditional Korean number.
Leap-day birthdays
If you were born on 29 February, your birthday falls on 28 February in years that are not leap years in this calculator. Some places treat 1 March as the legal birthday instead, so check the rule where you live if it matters for an official purpose. Your age in years, months and days is still counted correctly.
Frequently asked questions
How do I calculate my age from my date of birth?
Subtract your birth year from the current year, then subtract one more if your birthday has not happened yet this year. For months and days, count from your last birthday to today. The calculator does all of this for you.
How old am I if I was born in 2000?
Subtract 2000 from the current year. You are that age once your birthday has passed this year, and one year younger before it.
How many days old am I at 30?
A 30-year-old has lived about 10,957 or 10,958 days, depending on how many leap days fall in those years. Enter your date of birth for the exact number.
Why does another calculator show a different age?
Differences usually come from how month ends are counted, how a 29 February birthday is treated, or whether the time of birth and time zone are used. This calculator uses calendar dates and counts complete months and days.
How do I find the age difference between two people?
Choose Age difference, enter both dates of birth, and press Calculate. You get the gap in years, months and days, the total days, and who is older.
What is Korean age?
In the traditional Korean system a person is 1 at birth and adds a year every 1 January, so the number is usually one or two higher than the international age. South Korea officially moved to the international system for most legal uses in June 2023.
When will I be 10,000 days old?
About 27 years and 4 to 5 months after your birth. The Day milestones table in the results shows the exact date for your date of birth.
Does the calculator store my date of birth?
No. The calculation runs in your browser and the dates you enter are not sent to us.
About this calculator
This calculator counts complete years, months and days between two calendar dates using the Gregorian calendar. Day, week, hour and second totals come from the exact number of days between the dates. Last updated November 13, 2026. Questions or corrections: [email protected].
Written by Umar Khan
Umar Khan is a PhD student in engineering at NTNU, the Norwegian University of Science and Technology, in Norway. Every formula and worked example on this page is shown in full so you can check each result yourself. Corrections are welcome at [email protected].
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For information only, not professional advice.
Written by Umar Khan. Last updated: November 13, 2026.