Tool to compute the day number in a year, nth day of the year, the number of days since the first January in the Gregorian Calendar (N-th day).
Nth Day of the Year - dCode
Tag(s) : Date and Time
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The day of year calculator uses the number of days between the date of 1st january and the desired day. It takes into account the number of days in each month and if it is a leap year or not.
Automatic method: use dCode and indicate the day and month of a date, and if the year is leap year.
Example: The 1st January 2025 is the day 1
Example: The 31th december is the 365th (for non-leap year)
Manual method: count the days patiently or use the table:
50th day | 19/02 |
100th day | 10/04 |
123th day | 03/05 |
150th day | 30/05 |
183th day (365/2) | 02/07 |
200th day | 19/07 |
250th day | 07/09 |
256th day | 13/09 |
300th day | 27/10 |
350th day | 16/12 |
The calculation to be made is the date difference between 2 dates: the first day of the year and the current day.
A year has 365 or 366 days, the middle day of a year is the 183rd or July 2nd.
A calendar number is the (rare) name given to the day number in a year.
Type the formula =DATE(YEAR(TODAY()),1,A1) by replacing N with the day number to obtain the corresponding date in the current year. Replace YEAR(TODAY()) with any year value if needed.
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