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Every day counts

Date Calculator

Days between dates. A deadline 90 days away. The date six months ago. Get the answer, down to the weekday.

Count the days

Your result

31days

4 full weeks and 3 days

Friday, 1 January 2027
to Monday, 1 February 2027

Weekdays (Mon–Fri)
21
Weekend days
10

Earlier date included; later date excluded. Public holidays are not deducted.

Date calculator: days between dates and dates in the future

A date calculator answers two everyday questions: how many days are between two dates, and what date will it be after a certain number of days? Whether you are planning a holiday, checking the length of a project, counting down to a birthday or working backwards from an event, calendar arithmetic removes the guesswork. This free calculator uses the Gregorian calendar and accounts for different month lengths and leap years.

How many days between two dates?

The days between dates calculator counts the distance between your start and end dates. From 1 January 2027 to 1 February 2027 there are 31 days, or four full weeks and three days. This is an elapsed calendar-day count: one date to the next is one day. To count every date in a range, including both the first and last, select the inclusive option. The same January range then contains 32 dates.

Inclusive counting is useful when describing the dates covered by a trip or an event. Elapsed counting is useful for finding how far away a date is. For a same-day range, the default result is zero; with both dates included, it is one. A legal deadline, visa limit or contractual notice period may use its own counting rules, so check the relevant authority rather than assuming a general calendar count is the applicable rule.

What date is 30, 60 or 90 days from today?

To find 30 days from today, choose Add / subtract and enter 30 days with the other amounts set to zero. The same approach works for 60 days, 90 days or any other whole number. To find a date in the past, choose Subtract. Adding two weeks advances the date by exactly 14 calendar days, including weekends. The result shows the weekday so you can immediately see whether an event falls on a Monday or a Saturday.

Adding months and years is different from adding days

A month is not a fixed 30-day period. Adding one calendar month to 31 January 2027 gives 28 February 2027, the last valid day of February. Adding 30 days to that same start date gives 2 March 2027 instead. In a leap year, February has 29 days. A combined calculation applies years and months together first, adjusts an invalid month-end date to the last day of that month, and then adds or subtracts weeks and days.

This distinction matters for recurring milestones. Six calendar months and 180 days can end on different dates. Likewise, adding a year to 29 February 2028 gives 28 February 2029. Month-end adjustment is not always reversible: subtracting one month from that February date produces 28 January, not 31 January.

Calendar days, weekdays and business days

Calendar days include every date. Weekdays here are Monday through Friday. The separate weekday and weekend totals follow the same inclusion setting as the main result. Actual business days depend on the country, employer and local holidays; Saturdays and Sundays are not universal rest days. This tool does not deduct public holidays; the business days calculator does. Consult the 2027 country holiday calendars when planning around office closures.

Leap years and daylight saving time

A leap year has 366 days. In the Gregorian calendar, a year divisible by four is a leap year unless it is divisible by 100 but not by 400. That is why 2028 has a 29 February while 2100 does not. Calendar-day calculations also remain consistent across daylight saving changes: the dates before and after a clock change are still one day apart, even if only 23 or 25 real hours pass between local midnights.

If you need to compare actual clock times rather than dates, use the time zone converter. For a meeting involving several countries, the meeting planner compares local times on your chosen date.

Find the ISO week number for your result

The add/subtract result includes the ISO week number and ISO week-year. ISO weeks run from Monday to Sunday, and week 1 contains the first Thursday of the year. Near New Year, a date can belong to the previous or next ISO week-year. For example, 1 January 2027 belongs to week 53 of 2026, while week 1 of 2027 starts on 4 January. The 2027 week calendar lists the full Monday–Sunday range for each week.

Date calculator FAQ

How do I calculate the number of days between two dates?
Choose a start date and an end date. The calculator counts calendar days, including weekends and holidays. By default it includes the earlier date and excludes the later date. Select Include the end date to count both dates.
What date is 30, 60 or 90 days from today?
Use Add / subtract, set the start date to today and enter 30, 60 or 90 in Days. Keep Years, Months and Weeks at zero. The result includes the weekday and ISO week number.
Does the date calculator account for leap years?
Yes. February has 29 days in leap years and 28 otherwise. Years divisible by 4 are leap years, except century years unless they are also divisible by 400. So 2000 was a leap year, but 2100 will not be.
Is one month the same as 30 days?
No. Calendar months have 28, 29, 30 or 31 days. Adding one month to 31 January 2027 gives 28 February 2027; adding 30 days gives 2 March 2027.
Are weekends and public holidays excluded?
The total includes all calendar days. A separate weekday count excludes Saturdays and Sundays, but does not exclude public holidays. It is not a country-specific business-day calculator.
Do daylight saving clock changes affect the day count?
No. This tool compares calendar dates, not elapsed hours. A date remains one calendar day even when a local clock change makes that day 23 or 25 hours long.
What happens when I subtract months or choose an earlier end date?
Subtract moves the start date backwards. Calendar-month calculations clamp to the last valid day if necessary. In Days between dates, reversed dates give the same positive duration, with a note explaining that the end date is earlier.
What is an ISO week number?
ISO weeks start on Monday. Week 1 contains the year's first Thursday, so the ISO week-year can differ from the calendar year near New Year. The add/subtract result shows both the ISO week number and its week-year.