Inclusive date counting
Include both boundary dates for bookings, stays and deadlines.
DateGap • Calendar arithmetic
◴Date Difference Calculator: Days Between Dates
Calculate calendar days, weeks, weekdays and an exact age between two dates.
Top toolThree ways it saves you time
Business-day deadline
Project a weekday-only due date from the selected start date.
Swap and compare
Reverse the dates and see calendar, weekday and total-day gaps.
Elapsed difference
364 days52.0 weeks260 weekdays0y 11m 30d calendar gap
Business-day deadlineJan 15, 2026
Using this tool
Choose the count your situation needs
Choose a start and end date to get four useful views of the same period. Calendar days count every date, weekdays exclude Saturdays and Sundays, and the age view breaks the interval into calendar years, months and days.
Reading the output
Elapsed time is not always inclusive
January 1 to January 31
From 1 January to 31 January, the elapsed difference is 30 days. If you need to include both the first and last date in a booking or schedule, add one day to the result.
How elapsed days are counted
Elapsed days = end date − start date. Full weeks are the elapsed days divided by 7; remaining days are the remainder.
Deadlines need extra checks
- Use weekdays for a quick Monday–Friday estimate, not a legal business-day deadline.
- Public holidays are not removed because they differ by country.
- For birthdays, use the age result rather than dividing total days by 365.
Before relying on the result
Date-counting details
Does the calculator include the end date?
It shows elapsed time between the dates. Add one day when your situation needs inclusive counting.
Are public holidays excluded?
No. Weekdays remove Saturdays and Sundays only, since holiday calendars vary by location.