Date Difference Calculator
Count the exact time between two dates — years, months, days, weeks, business days, and hours.
Fill in the fields above to see your result instantly.
This date difference calculator measures the duration between any two dates. It counts the exact calendar span as years, months, and days — borrowing the real length of each month and accounting for leap years — and also gives you the total in days, weeks, and hours. The business-days figure counts only Monday to Friday, which is handy for project timelines and notice periods. Enter the dates in any order; the calculator measures the gap between them.
How to use the Date Difference Calculator
- 1
Enter the start date
Pick the earlier date — or either one; order doesn't matter.
- 2
Enter the end date
Pick the other date you want to measure to.
- 3
Choose how to show it
Switch between years/months/days, weeks and days, total weeks, or total days. Pick the count method — exclusive for elapsed days, inclusive to count both the first and last day. Results are instant.
Examples
Date Difference Calculator FAQs
How do you calculate the number of days between two dates?
The calculator converts both dates to a day count and subtracts them, giving the exact number of whole days between the two — then derives weeks, months, and hours from that span.
What counts as a business day?
Business days are Monday through Friday. The business-days figure excludes Saturdays and Sundays but does not account for public holidays, which vary by country.
Does the calculator include both the start and end dates?
By default it uses the exclusive count — the elapsed days between the two dates. Switch the count method to "Include end date" to count both the first and last day, which adds one day to the total. Use inclusive counting for deadlines, notice periods, and booking windows where the final day still counts.
Can I enter the dates in either order?
Yes. The calculator always reports the absolute duration, whichever date you put first.