Date Calculator

Count days between dates, add days to a date, or count working days.

Result
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    How it works

    The method

    Days between two dates are counted on the calendar, so month lengths and leap years are included. A year is a leap year when it divides by 4, except years that divide by 100 but not by 400.

    Worked example

    From 1 January 2025 to 1 March 2025 is 59 days (31 + 28). The same dates in 2024 are 60 days apart, because February 2024 had 29 days.

    Common mistakes

    Decide whether the end date counts: counting both the first and the last day adds 1. For working days, choose your country’s weekend and add your holidays.

    Questions & answers

    Why is the answer empty?

    Choose the day, the month and the year for every date. In Add / subtract, enter at least one number of years, months, weeks or days.

    Should I tick “Count the end date too”?

    Tick it when both days count, like the days of a holiday or a contract: 1 to 31 January is then 31 days. Leave it off to count the days in between, like a countdown: 1 to 31 January is 30 days.

    Why is 31 January plus 1 month 29 February, not 2 or 3 March?

    Adding a month keeps you in the next month. When that month is shorter, its last day is used (29 February in a leap year, otherwise 28 February). The page tells you when this happens.

    My country's weekend is Friday and Saturday. How do I count working days?

    In Working days, choose your weekend in the list: Saturday + Sunday, Friday + Saturday, only Friday, only Sunday, or no weekend. Both dates are counted.

    Are public holidays taken out of working days?

    Only the ones you write in the Holidays box. Holidays are different in every country and region, so none are added by themselves: write yours one date per line (YYYY-MM-DD) and every one that falls on a working day is taken out.

    What is the ISO week number?

    Weeks start on Monday, and week 1 is the week with the first Thursday of the year. So 31 December 2024 is in week 1 of 2025. This is the numbering used in Europe and in most diaries.

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