Days Between Dates Calculator
Enter any two dates to see the total day span, calendar year-month-day breakdown, full weeks, weekdays and weekend dates under an explicit counting rule.
Standard elapsed-date counting excludes the start boundary. The result is shown as an absolute span.
Context matters.
- A day-only calculation uses Gregorian calendar dates, not 24-hour timestamps, so daylight-saving transitions do not change this result.
- Use the Business Days mode when weekends or U.S. federal holidays must be excluded.
Sources & scope
The calculation guide and this source trail show what the result means, where the rule came from and when it was last reviewed. This is source-and-calculation QA, not a claim of medical, legal, tax or other professional review; time-sensitive decisions still belong with the linked authority.
See both the exact day total and the calendar story.
A total-day difference and a calendar-unit breakdown answer different questions. CalcSpan shows both without converting a plain date through a local time zone.
- 01Enter two dates
The calculator accepts either order and can show an absolute or signed result.
- 02Choose inclusive or elapsed
Standard elapsed counting excludes the start boundary; inclusive counting adds both endpoint dates.
- 03Read every unit
Compare total days with whole calendar years/months/days, full weeks, weekdays and weekends.
Total days is the count of Gregorian date boundaries, with one extra day only when inclusive counting is enabled.
Whole years and months are advanced from the earlier date using a last-valid-day clamp before the remaining days are counted.
The weekday figure uses Monday through Friday and does not remove holidays; use Business Days for holiday-aware counting.
Rule set 2.0.0. Last reviewed 2026-08-22. Next review due 2027-02-22.
What to know before using the result.
How many days are between two dates?
By default, CalcSpan subtracts the start date from the end date, so consecutive dates are one day apart. Inclusive counting makes those same two dates count as two calendar dates.
Why can years, months and days differ from total days?
Calendar months have different lengths. The calendar breakdown advances whole years and months first, while total days counts every date boundary.
Are leap years included?
Yes. Gregorian leap days are part of both the total-day result and the calendar-unit breakdown.
Does this result remove weekends or holidays?
It shows weekday and weekend context but does not remove holidays. Switch to Business Days mode for exclusions.