How to count days between two dates
Count calendar days between two dates without losing or double-counting the day a month changes.
Short answer
The distance is the number of midnights between the dates. The order does not matter. If your contract counts both endpoints, add one and say that you did.
Decide what “between” includes
From March 1 to March 3 is two days if you mean the gap, and three dates if you mean a list of the days touched. Hotel nights, prescription days, and “business days” each pick a different convention. This site’s tool returns the gap. Business days are a different problem because weekends and holidays are not in the subtraction.
A leap day counts when it falls strictly inside the gap. From 1 January 2024 to 1 March 2024 is 60 days, not 59, because 2024 has a February 29. Impossible dates such as 31 February should be rejected rather than rolled into March.
Common mistakes
- Adding one for inclusivity and also starting the count on the first day.
Frequently asked questions
- What about weekends?
- They are included. This is a calendar span, not a business-day span.
Related
- Days between datesCount the days between two calendar dates, including neither extra day beyond the span you picked.
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