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With the calendar countdown calculator, you can quickly find the number of days in a countdown between two dates. Keep reading this short article; here you'll learn:

  • A brief introduction to calendars.
  • How to calculate a calendar countdown;
  • An example of calculating the days in a calendar countdown between two random dates; and
  • Similar tools that may help you with keeping track of time!

A brief history of the calendar

The calendar we use today all across the world is the Gregorian calendar from the pope's name, under which this time-keeping system was used in most European territories and then worldwide. Its introduction is relatively recent: 1582! Before the Gregorian calendar, the Julian calendar was in use, but the change was deemed necessary because it had minor flaws. The Julian calendar is still in use in the Orthodox Church, though!

Farther in time, we can meet more variegated examples of calendars: from the rudimentary calendar used by Romans, to which we owe the creation of September, November, and December, to the curious way the Mayans used to keep track of time.

Today's calendar is a way to subdivide 365 days (or 366, if we are dealing with a leap year) into 12 months of various duration. This quirk makes counting the number of days between two dates possible: in the next section, you'll learn how to calculate a calendar countdown quickly!

How to calculate a calendar countdown: days between two dates

After you choose a starting and a final date, you can start calculating your calendar countdown of days right away. Follow the next steps:

  1. Check if the starting date and the final date are in order and in the same month: if yes, your countdown will be pretty short! Subtract the final day number from the number of the day after your starting date (we make the countdown start from "tomorrow"). You are done!
  2. If the starting and final dates are not in that lucky position, start by counting the number of days in the starting month. Subtract the number of the day after the starting date from the duration of the starting month in days.
  3. Proceed by counting the number of days in the final month. It's enough to take the day number of the final date.
  4. Check if, between the final and initial date, there are complete years (at least twelve full months, or multiples of this number). If yes, consider 365 days for each complete "normal" year and 366 days for each leap year.
  5. Count the number of days in the remaining full months between the final and the starting date. In this case, you need to be careful and check with the mnemonics thirty days hath September... if necessary!
  6. Sum all the contributions you found in the previous steps. You are done! Start counting, and every morning subtract one from the total: you'll reach zero on your final date.

An example of calculating a calendar countdown

Take two random dates, the 8th September and the 17th July of the previous year. We are not dealing with leap years.
To count the days in this calendar countdown:

  1. Count the days in July: subtract 18 from 31: 3118=1331 -18 = 13.
  2. Count the days in September: 88.
  3. There is a full year (from August to August) between the two dates, so consider it in your result: add 365365 days.
  4. There are no months left! As August comes right after July and before September, we don't need to count anything else.
  5. Sum the results: 13+8+365=38613+8+365 = 386 days.

That's it!

More tools to calculate date differences and countdowns

If our calendar countdown calculator helped you, you may find our other dedicated tools useful too: you can find tools with presets or tools where every input is in your control. Try our:


How do I calculate the days in a calendar countdown?

To calculate the number of days in a calendar countdown, follow these easy steps:

  1. Choose the final and the initial date.
  2. Count the number of days in the initial and final month. Consider the day after the starting date to set up a proper countdown and the durations of the months.
  3. Check for complete years between the dates, and add 365 days or 366 days (for leap year) for each.
  4. Sum the days in the remaining months (not belonging to a complete year).
  5. Sum all the results.

How many days are between the first of April and Halloween?

There are 212 days between the first of April and Halloween. To find this result:

  1. Find the number of days in April: April has 30 days, and we start counting from the 2nd: 30 - 2 = 28 days.
  2. Find the days in October: 31 days.
  3. Count the days in the months between (May, June, July, August, and September): 31 + 30 + 31 + 31 + 30 = 153 days.
  4. Sum all the contributions: the result is 28 + 31 + 153 = 212 days.
Davide Borchia
0 years,
313 days,
6 hours,
48 minutes,
4 seconds
until the final date! 🕜📅
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