Calculate the exact duration between any two dates — in years, months, weeks, days, hours, minutes, and seconds. Includes working days and weekends.
Exact Duration
Showing June 2026
How is the date difference calculated?
We calculate the exact difference in years, months, and days using calendar arithmetic, then convert to other units (hours, minutes, seconds) from the millisecond difference.
Does this count working days?
Yes. Working days are Monday through Friday. Weekend days are Saturday and Sunday. Public holidays are not excluded as they vary by country.
What if I enter a future end date?
The calculator works for any two dates — past, present, or future. It shows the absolute duration between them.
How are total hours calculated?
Total hours = total milliseconds difference ÷ 3,600,000. This is the actual number of hours between the two datetime moments.
Can I calculate project duration?
Yes. Enter your project start and end date to get the exact duration including working days, total days, and all time breakdowns.
Why does the working days count include both dates?
We count both the start and end date as part of the range. If you want to exclude one, subtract 1 from the working days result.
What is the difference between days and working days?
Total days includes every calendar day (weekdays + weekends). Working days only counts Monday through Friday.
Can I use keyboard shortcuts to change dates?
Yes. Once a date field is focused, you can use arrow keys to increment or decrement the day, month, or year.