Free date calculator: count the days between two dates, add or subtract days from any date (for example 100 days from today), and build a live countdown timer.
Free date calculator: count the days between two dates, add or subtract days from any date (for example 100 days from today), and build a live countdown timer. Use it for everyday work, development, learning, or quick verification.
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Working out how many days lie between two dates sounds simple, yet answers are often off by one because people count differently. This tool reports end date minus start date, so 1 January to 3 January is 2 days. If you need an inclusive count that includes both the first and last day, as for leave, hotel stays or event periods, add 1 to get 3 days. The order of the two dates does not matter, since the tool uses the absolute difference, and it also breaks the result into years, months and days for readability.
Date offset mode counts forwards or backwards from any day: enter a positive number to move into the future or a negative number to go back. Typical uses include contract deadlines, a 90-day probation period, a 14- or 30-day return window, visa stay limits, a baby’s 100th day and pregnancy week counts. Because it counts calendar days, weekends and public holidays are included; for business days you need to subtract them separately.
Calendar rules shape the result. A common year has 365 days and a leap year 366. A year is a leap year if it is divisible by 4, except that century years must also be divisible by 400, so 2000 was a leap year, 1900 was not, and 2028 is the next one. Months differ in length too, with February having 28 or 29 days, so adding one month is not the same as adding 30 days. This tool always counts exact days to avoid that ambiguity.
Countdown mode shows the days, hours, minutes and seconds remaining until a target date in real time, ideal for exams, weddings, product launches or New Year’s Eve, and you can copy the countdown to share it. Once the target has passed, it shows how much time has elapsed instead. All calculations run in your browser using your device’s local time.
This tool calculates end date minus start date, so 1–3 January is 2 days. For inclusive counts such as leave or hotel nights plus the checkout day, add 1.
Choose Date Offset, set today as the start date and enter 100. Weekends and holidays are included because the tool counts calendar days.
It must be divisible by 4, and century years must also be divisible by 400. So 2000 was a leap year, 1900 was not, and 2028 is the next one.
It counts calendar days, including weekends and public holidays. To get business days, subtract the weekends and holidays in that period from the result.
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