DateAndTimeCalculator.org

Days Between Dates Calculator

Count the number of days between two dates, with the option to include or exclude the start and end dates, plus a weekday breakdown.

Last reviewed: 30 July 2026

Which days to count

Counting neither gives the elapsed days between them; counting both gives the number of days the period covers.

How this calculation works

Each date is converted to a count of whole days since a fixed reference point, and one count is subtracted from the other. Because the comparison happens in whole days rather than in clock time, the answer is never affected by daylight saving or by which time zone you are in.

Counting the endpoints

The gap between two dates and the number of days a period covers are different numbers, and confusing them is the most common source of off-by-one errors. From Monday to Friday is four days of elapsed time but five days of working week. Both tick boxes are shown so you can be explicit about which you mean, and the result repeats your choice back to you.

Leap years

Every 29 February inside the range is counted. A year is a leap year when it divides by four, except century years, which must divide by 400 — so 2000 was a leap year but 1900 and 2100 are not.

Worked example

From Monday 5 January 2026 to Friday 9 January 2026

  • 4 days counting neither endpoint
  • 5 days counting the last day only
  • 5 days counting the first day only
  • 6 days counting both

A working week booked off as annual leave is five days, which is the “count the last day” reading with the first day already included by the start date itself.

Limitations

  • Every calendar day is counted, including weekends and public holidays.
  • Times of day are ignored; the calculation works on whole dates only.
  • Dates use the Gregorian calendar throughout, including for years before it was adopted locally.

Frequently asked questions

Should I count both the start and end dates?

It depends on the question. For "how many days until my deadline" you want the elapsed count, which excludes the start day. For "how many days is my holiday" you want both endpoints counted. The two tick boxes let you choose, and the result always states which reading it used.

How many days are there between two dates in different years?

The calculator counts every real day, so leap days are included automatically. From 1 January 2027 to 1 January 2029 is 731 days rather than 730, because 2028 is a leap year.

Can I exclude weekends?

Not on this page, which counts every calendar day. The working days between dates calculator excludes weekends and, if you choose a country, public holidays as well.

What is the weekday breakdown for?

It shows how many Mondays, Tuesdays and so on fall in the range. This is useful for counting shifts, weekly classes, rent periods or anything else that happens on a fixed day of the week.

Does the order of the dates matter?

No. If you enter the later date first the calculator still gives the same number of days and tells you the range runs backwards. Use the swap button to reverse them.