Days Between Dates Calculator

Count the days between two dates and see the period as years, months and days. You can choose whether the first day is included.

Start date

End date

First day

Days — days

In weeks—

In years, months and days—

The copied value is the number of days, without commas.

How days are counted

Days: with "Do not include", the result is the end date minus the start date (October 18 to October 19 is 1 day). With "Include", one day is added: the start date counts as day 1.
Years, months and days: years and months are added to the start date as far as possible without passing the end date, and the remainder is the days. If the month you land in does not have that day, the last day of the month is used (one month after January 31 is February 28, or February 29 in a leap year).
With "Include", the day after the end date is used as the end point, and both the days and the years, months and days are counted the same way.

How the days between two dates are calculated

The number of days is the end date minus the start date, counted on the calendar, including the different month lengths and leap years (years in which February has 29 days).

From October 18, 2026 to December 31, 2026 is 74 days.
From January 1, 2026 to December 31, 2026 is 364 days, or 365 days if the first day is included.
From January 1, 2000 to October 18, 2026 is 9,787 days.
From February 28, 2024 to March 1, 2024 is 2 days because 2024 is a leap year (it would be 1 day in 2023).

Including or excluding the first day

There are two common ways to count. The default here is not to include the first day, which gives the difference between the two dates. Including the first day counts the start date as day 1, which is how many deadlines and "N-day" periods are counted. Check which convention your situation uses.

Notes

Dates can be entered from January 1, 1900 to December 31, 2100. Dates are calculated on the Gregorian calendar, using the dates as entered, with no time zones or times of day.
If your browser shows a text box instead of a date picker, enter the date as YYYY-MM-DD (for example 2026-10-24). Dates such as 03/04/2026 are not accepted, because they can mean March 4 or April 3.
If the end date is before the start date, the dates are swapped and a note is shown.

Frequently asked questions

How many days are there between two dates?

Enter the start and end dates. The result is the number of days between them, not counting the first day by default.

Does the calculator include the start date?

Not by default. Choose "Include" under "First day" to count the start date as day 1.

Does it handle leap years?

Yes. February has 29 days in leap years, and the count follows the real calendar.