Instantly calculate exact age in years, months and days from any date of birth. Get live results, a full breakdown into every time unit, a batch tool for comparing multiple birth dates, and a dedicated calculator for the gap between any two dates — not just birth to today.
Date of birth cannot be after the "Calculate As Of" date.
This calculator works out your exact age by comparing your date of birth to today's date, or to any other date you choose. Results update live and include a full breakdown into years, months, weeks, days, hours, minutes and seconds, plus a countdown to your next birthday. Everything runs in your browser — no dates are sent to or stored on our servers.
Your exact age, converted into every time unit.
| Unit | Value |
|---|
Calculate ages for a whole list of people at once. Enter one date of birth per line (YYYY-MM-DD) — useful for classrooms, HR records, or family trees.
Find the exact gap between any two dates — not just a birth date and today. Useful for the age gap between siblings or partners, time until an anniversary, or the length of a project.
| Step | What Happens |
|---|---|
| 1. Compare years | The number of full years between the birth year and the reference year is counted. |
| 2. Compare months | If the reference month falls before the birth month, one year is borrowed and 12 is added to the month count. |
| 3. Compare days | If the reference day falls before the birth day, one month is borrowed using the actual number of days in the previous month. |
| 4. Leap years | Because real calendar months and days are used (not a fixed 365-day year), leap years are handled automatically and correctly. |
| 5. Total days | A separate exact day-count between the two dates gives total days lived, which is then converted into weeks, hours, minutes and seconds. |
Ages that commonly mark a legal or cultural milestone (varies by country):
| Age | Commonly Associated With |
|---|---|
| 13 | Becomes a "teenager" |
| 16 | Minimum driving age in many countries |
| 18 | Legal adulthood in most countries |
| 21 | Full legal adult age in the US and others |
| 30 | End of "young adult" in many surveys |
| 60–65 | Common retirement age range |
| 100 | Centenarian |
Roughly how many days, weeks and hours you've lived at common ages (based on a 365.25-day average year):
| Age | ≈ Days Lived | ≈ Weeks Lived | ≈ Hours Lived |
|---|
| Generation | Birth Years | Notes |
|---|---|---|
| Generation Alpha | 2013–2024 | Children of Millennials |
| Generation Z | 1997–2012 | First fully digital-native generation |
| Millennials | 1981–1996 | Also called Generation Y |
| Generation X | 1965–1980 | Grew up between analog and digital |
| Baby Boomers | 1946–1964 | Born during the post-war population boom |
| Silent Generation | 1928–1945 | Came of age during WWII |
Generation ranges are approximate and vary slightly between researchers (this table follows commonly cited Pew Research ranges). Enter a birth date in the calculator above to see the exact age — generation labels are just a fun way to place it in cultural context.
Type or pick the date of birth you want to calculate age for.
Leave it on today, or choose another date to calculate age as of that day.
Exact age in years, months and days appears instantly.
View your age converted into weeks, hours, minutes and seconds, or compare multiple dates with the batch tool.
From a single exact age to comparing a whole list of birth dates, get accurate results in seconds — plus a dedicated tool for the gap between any two dates. Explore our full library of free calculator templates.