Date Difference Calculator
Count signed calendar days between two dates and break the absolute interval into weeks and days.
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How to use Date Difference Calculator
Measure a date interval without daylight-saving surprises. The result counts midnight-to-midnight calendar boundaries, with a signed day count for chronological order and an absolute duration for planning.
- Choose the starting calendar date.
- Choose the ending calendar date.
- Calculate the signed difference and the absolute weeks-and-days interval.
Good to know
- The count excludes the starting day: January 1 to January 2 is one day. It is not an inclusive count of dates.
- Dates use the proleptic Gregorian calendar and UTC arithmetic. Business days, holidays, local calendar reforms, and time-of-day differences are not calculated.
Common questions
What if the end date is earlier?
The signed calendar-day result is negative. The absolute result and the weeks-and-days breakdown remain nonnegative.
Does daylight saving affect the result?
No. Each input is treated as a calendar date at midnight UTC, rather than as a local clock time.
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