Tinker Calc

Tools › Dates & Time

Days Between Dates Calculator

Enter a start date and an end date to see how many days lie between them, along with the total in weeks, a years-months-days breakdown and the number of weekdays (Monday to Friday).

Tick this for inclusive counts such as event or rental days
Total days–
Total weeks–
Years, months and days–
Weekdays (Mon–Fri)–

How to use it

Pick a start date and an end date. The result updates instantly. By default the calculator counts the days from the start up to, but not including, the end date—the same way you count nights in a hotel stay or the age of something. Tick 'Include the end date' when both days should count, for example a festival running Friday to Sunday (3 days).

How the count works

Both dates are read as midnight UTC, so daylight saving changes never add or lose an hour. The difference in milliseconds is divided by 86,400,000 (milliseconds per day). Weeks are days divided by 7. The years-months-days breakdown steps forward in whole calendar months, borrowing the length of the previous month when the day number would go negative. Weekdays count every Monday to Friday in the range; public holidays are not removed because they vary by country.

Worked example

From 1 January 2024 to 1 March 2024: January has 31 days and February 2024 has 29 (a leap year), giving 60 days. That is 8.57 weeks, or exactly 2 months. Eight full weeks contain 40 weekdays, and the remaining 4 days (Monday to Thursday) add 4 more, for 44 weekdays. With 'include end date' ticked the total becomes 61 days.

Tips

For deadlines like '30 days from today', count without the end date. For leave or rental days, include it. If the end date is earlier than the start, you'll see a negative number showing how many days ago it was. Subtract your local holidays from the weekday figure to get working days.

Frequently asked questions

Does it account for leap years?

Yes. It uses real calendar dates, so 29 February is counted whenever it falls in the range.

Should I include the end date?

Include it when both the first and last day are 'used', such as holidays or events. Leave it off for elapsed time, like ages or loan periods.

Are public holidays excluded from weekdays?

No. Holidays differ by country and region, so only Saturdays and Sundays are excluded. Subtract holidays yourself.

Why is a month not always 30 days?

Calendar months run 28 to 31 days, so the breakdown follows the actual calendar rather than a fixed length.