Date Difference Calculator
Find days, weeks and calendar difference between two dates.
Days between two dates
This tool calculates elapsed time between two calendar dates.
Common uses
Use it for projects, delivery windows, travel planning and anniversaries.
Calendar difference and elapsed days
The number of elapsed days between two dates is not always the same as a calendar difference stated in years, months and days. Calendar months have different lengths, while elapsed days is a fixed count of day boundaries between the selected dates.
Inclusive vs exclusive date counting
Some schedules count both the start and end date while others count only the time between them. Make sure the counting convention matches your use case, especially for bookings, leave, deadlines and billing periods.
Frequently Asked Questions
Are both dates counted?
The total-day result measures elapsed time. Add one day for an inclusive count.
Why can two date ranges with one month difference contain different numbers of days?
Calendar months contain 28, 29, 30 or 31 days, so a one-month calendar difference does not represent a fixed number of days.
Should I count the start date?
It depends on the rule you are following. Elapsed-time calculations usually exclude the starting instant, while some schedules and attendance rules use inclusive counting.