UltimateTools
Time & Date

Days Between Dates

Calculate the exact number of days, weeks, or months between any two dates, including or excluding the end date.

Choose a start and end date to calculate the difference.

How the Days Between Dates works

Choose a start and end date and the calculator instantly works out the total number of days, weeks, and the exact years/months/days breakdown between them. It also splits the total into weekdays (business days) and weekend days, which is useful for planning deadlines, contracts, or trips.

Frequently asked questions

Does this count the start and end date?

By default, only full days between the two dates are counted. Check "Include both the start and end date" to count them as well.

What counts as a business day?

Business days are Monday through Friday. This tool doesn't currently exclude public holidays.

Can I use this to count days until a future date?

Yes — set the start date to today and the end date to any future date to see exactly how many days remain.

Guides that cover this

Mastering Dates, Deadlines, and Time ZonesThe everyday date math — ages, countdowns, business days, time zones — that's easy to get wrong by hand.Counting Days Between Two Dates: Inclusive vs. Exclusive, With ExamplesA worked example showing how the same two dates can produce two different, both-correct day counts depending on the counting convention used.Why Your Manual Day Count Was Off by One DayThe specific inclusive-vs-exclusive counting mistake that causes a hand-calculated day count to be off by exactly one.Calendar Days vs. Business Days Between Two DatesWhy the same two dates produce a smaller business-day count than calendar-day count, and when each is the right measure.How to Use Days Between DatesA quick walkthrough of calculating the exact days, weeks, and months between two dates.Days Between Dates: How It Works and How to Use ItA quick guide to the days between dates — what it calculates, how the math works, and tips for getting an accurate result.

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