Understand the result
How to use the date difference calculator
Compare two calendar dates in total days, full weeks and weekdays for deadlines, travel or project planning.
Formula or method
Dates are normalized to calendar values; the difference in milliseconds is divided by one day. Weekdays count Monday through Friday.
Worked examples
One full week
September 1 to September 8 is seven elapsed calendar days, or one full week.
A project deadline
October 2 to October 20 is 18 calendar days; the weekday count excludes Saturdays and Sundays.
Dates in reverse order
If the dates are entered in reverse, the tool still reports the absolute distance between them.
Frequently asked questions
Does the result include both the start and end date?
The main result measures elapsed time between the two dates. Counting both dates as occupied calendar dates would add one.
What is the difference between calendar days and weekdays?
Calendar days include every day. Weekdays include Monday through Friday only.
Are public holidays removed?
No. Holiday calendars vary by country and region, so only weekends are excluded from the weekday figure.
Can daylight saving change the result?
Dates are normalized for calendar comparison, which avoids most one-hour daylight-saving shifts affecting the day count.
Limitations
Country-specific public holidays are not excluded.