Date Difference Calculator - Days Between Dates
Calculate the calendar span between two dates in days, weeks, months, or years, with an option to include the end date.
How the Date Difference Calculator Works
Compare any two calendar dates and see the elapsed interval expressed independently as complete days, weeks, months, and years.
Use the optional inclusive setting when both the start date and end date should count toward a booking, event, leave period, or other date range.
Frequently Asked Questions
- Does this include the end date?
- By default, the end date is excluded (meaning the difference between today and tomorrow is 1 day). You can toggle the "Include end date" checkbox to add 1 day to the result.
- Is it accurate for leap years?
- Yes, the calculation uses a robust date library that correctly handles leap years and variable month lengths.
- Can the end date be earlier than the start date?
- Yes. The calculator uses the absolute difference, so swapping the start and end dates produces the same positive duration.
- Why does the month result not equal days divided by 30?
- Calendar months have different lengths. The month result counts complete calendar-month periods between the selected dates instead of treating every month as 30 days.
- What is the difference between this and the time-between-dates calculator?
- This calculator compares date-only values and focuses on calendar days, weeks, months, and years. Use Time Between Two Dates when the hours, minutes, and seconds of each timestamp matter.
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