Calculate the exact age or date difference between any two dates in years, months, weeks, and days. Useful for age gap comparisons, anniversaries, project durations, and date math.
Use this age calculator between two dates to find exact age or the exact time between any two dates. It also works as a date difference calculator and an exact duration calculator.
Choose Age Calculator, Date Difference, or Exact Duration at the top, then enter the start and end dates. The calculator updates live and shows the result in years, months, days, and totals that are easy to compare.
- Weekday born: —
- Zodiac: —
- Chinese zodiac: —
- Start date:
— - End date:
—
- Years: —
- Months: —
- Days: —
- Years: —
- Months: —
- Weeks: —
- Days: —
- Days (including end date): —
- Hours: —
- Minutes: —
- Seconds: —
Examples
- Age calculator: enter a date of birth and today as the reference date.
- Date difference: enter any two dates to see the exact gap between them.
- Exact duration: enable time fields to include hours and minutes in the result.
How age calculation works
Age mode treats the first date as the starting point and the second date as the reference date. The calculator counts complete calendar years, then months, then days, so the result stays exact even when the two dates do not line up to whole months.
If you enable time, the calculator also keeps hours and minutes in the result. That is useful when you need an exact age or exact duration with a timestamp instead of just a date.
How date difference is calculated
Date difference uses the same underlying calendar math, but the result is interpreted as the gap between two chosen dates. The calculator also shows totals in days, weeks, months, hours, and minutes so you can quickly compare a schedule, deadline, or project period in the unit that matters.
The optional include-end-date switch shows the inclusive day count when you need to count both the start and end dates in the total.
Related calculators
Frequently asked questions about the age and date difference calculator
How does age calculation work?
Age mode treats the first date as the starting point and the second date as the reference date. The calculator counts complete years, then months, then days, so the result stays exact.
How is date difference calculated?
Date difference uses the same calendar math but interprets the result as the gap between two selected dates. It also shows total days, weeks, months, hours, and minutes.
Can I include the end date?
Yes. Turn on Include end date when you need the day count to include both the start and end dates.
Can I include the time of day?
Yes. Turn on Include time to add hours and minutes to the calculation for a more precise result.
