Date Calculator

How to use the Date Calculator

1. To count the time between two dates, pick a start date and an end date. Tick "include the end date" if both days should count, such as for a hotel stay or an event that runs through the last day.
2. To find a future or past date, pick a start date, choose Add or Subtract, and enter any mix of years, months, weeks and days.
3. The result shows the full date with the day of the week.

How it's calculated

Total days are the difference between the two dates on the calendar, using UTC so daylight-saving changes never add or drop an hour. Business days count Monday through Friday only. Public holidays aren't excluded, since they vary by country and employer.

When adding months, the day of the month stays the same if possible. If the new month is shorter, the result moves to its last day, so January 31 plus one month is February 28 (or 29 in a leap year).

Frequently asked questions

Does it count the start date or the end date?
By default it counts the days in between the way a calendar does: Monday to Tuesday is 1 day. Tick "include the end date" to count both days, so Monday to Tuesday becomes 2.

Are holidays excluded from business days?
No. Business days here are Monday to Friday. Subtract any public holidays in your range yourself, since they differ by country and company.

Does it handle leap years?
Yes. February 29 is counted in leap years, and adding a year to February 29 lands on February 28 when the next year isn't a leap year.