Talk:Leap year

section Algorithm: adding Excel example

 * Algorithm

The following pseudocode determines whether a year is a leap year or a common year in the Gregorian calendar (and in the proleptic Gregorian calendar before 1582). The year variable being tested is the integer representing the number of the year in the Gregorian calendar, and the tests are arranged to dispatch the most common cases first. Care should be taken in translating mathematical integer divisibility into specific programming languages.

if (year is not exactly divisible by 4) then (it is a common year) else if (year is not exactly divisible by 100) then (it is a leap year) else if (year is not exactly divisible by 400) then (it is a common year) else (it is a leap year)

This algorithm translates into Excel like this, whereas year stands for the cell which refers to the input cell:
 * Excel

=IF(NOT((year/4=TRUNC(year/4)));"common year";IF(NOT((year/100=TRUNC(year/100)));"leap year";IF(NOT((year/400=TRUNC(year/400)));"common year";"leap year")))

or reversed, more simplified:

=IF((year/400=TRUNC(year/400));"leap year";IF((year/100=TRUNC(year/100));"common year";IF((year/4=TRUNC(year/4));"leap year";"common  year"))

-- 23:17, 20 August 2015 31.151.83.20


 * Fine, but an Excel formula is not the sort of thing WP would ordinarily supply. The shape of the algorithm in pseudo-code is appropriate, but translations into specific languages generally not. -- Elphion (talk) 17:51, 26 August 2015 (UTC)

Section "Algorithm" - why?
Can anyone provide a convincing case for retention of the section. It looks to me like one editor's pet project. At, we already have the concise statement "Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400. For example, the years 1700, 1800, and 1900 are not leap years, but the years 1600 and 2000 are." with a sensibly-sized graphic beside it. What value does this "Algorithm" section add over and above what has been said already? How is it not a WP:NOTMANUAL violation? Furthermore its suggestion that it has any validity before 1582, let alone in the years BC/BCE, is surely just wrong? 𝕁𝕄𝔽 (talk) 11:17, 21 December 2022 (UTC)
 * Pending discussion, I have moved it to the end of the article where at least it (and its giant graphic) are not so disruptive. --𝕁𝕄𝔽 (talk) 13:21, 21 December 2022 (UTC)
 * The section seems redundant to me Jc3s5h (talk) 01:27, 22 December 2022 (UTC)

As no case has been made to retain that section, I have deleted it. 𝕁𝕄𝔽 (talk) 23:57, 29 December 2022 (UTC)


 * Could the section be moved to https://en.wikipedia.org/wiki/Leap_year_problem, where there is now a dead link to the algorithm? 2A02:8010:6008:0:A829:F7:2B5D:F60 (talk) 10:27, 19 September 2023 (UTC)

What citation format?
In the archives there is a thread about this, Talk:Leap year/Archive 3. I believe what was said there still holds, use citation rather than. However, when formats where the elements of the citation are separated by commas, as with the Chicago Manual of Style footnote style, are used for the endnotes, bibliographies commonly separate the elements with periods. Since the Sources section resembles a bibliography, I have left the "cite xxx" templates there as they were. Jc3s5h (talk) 16:37, 7 August 2023 (UTC)

certain trees and plants bear twice during a leap year
i have noticed on my farm in trinidad many of my plants and fruit trees bear twice during a leap year i am from a tropical country in the carribbean can anyone contest to this? Gramchees (talk) 12:13, 20 August 2023 (UTC)


 * This is strictly anecdotal, and not very credible as a general phenomenon. A reliable source would help. -- Elphion (talk) 16:25, 20 August 2023 (UTC)

Repeated information
I think that the information is repeated in this article. We have first a section called "Julian calendar" and, then, another one called "Julian reform" with the same information but more elaborated. It would be interesting to merge if you agree that it is a repetition. Theklan (talk) 10:22, 31 January 2024 (UTC)


 * I'll look closer. But in the mean time, I restored Theklan's removal of the section on the Revised Julian calendar because that is different from the Julian calendar. Jc3s5h (talk) 16:15, 31 January 2024 (UTC)

Changing content
This edit: https://en.m.wikipedia.org/w/index.php?title=Leap_year&diff=prev&oldid=1230828637

was reverted for some unknown reason. How could we handle this and keep it as the current form, with the example as Halloween and not Christmas? 2601:C6:D200:E9B0:99C2:CF40:D108:35E0 (talk) 00:18, 25 June 2024 (UTC)
 * The person wanting a change needs to justify their proposal. It is not reasonable to expect other to justify reverting arbitrary changes. Johnuniq (talk) 00:22, 25 June 2024 (UTC)
 * A lot of people in the world have no idea what, and when, Halloween is. - Arjayay (talk) 09:21, 25 June 2024 (UTC)
 * So how about we compromise and change the example to a very specific day? 2601:C6:D200:E9B0:A0E3:7891:AA06:7FAE (talk) 16:39, 25 June 2024 (UTC)
 * I’ll go make that edit. 2601:C6:D200:E9B0:A0E3:7891:AA06:7FAE (talk) 16:40, 25 June 2024 (UTC)
 * The edit has now been made. 2601:C6:D200:E9B0:A0E3:7891:AA06:7FAE (talk) 16:43, 25 June 2024 (UTC)
 * Maybe we could remove the example all together as a neutral compromise? I’ll make that edit now. 2601:C6:D200:E9B0:A0E3:7891:AA06:7FAE (talk) 16:50, 25 June 2024 (UTC)
 * I have reverted your totally undiscussed removal, made with an edit summary of "as discussed on talk page". You suggested it and immediately did it before anyone else had had a chance to discuss it. - Arjayay (talk) 21:04, 25 June 2024 (UTC)
 * If 14 Feb 2024 already passed, and naming holidays would cause an argument, it would make sense to specifically mention March 1st as a notable example, as that day immediately follows February 29 in leap years.Allan Bao (talk) 14:24, 15 July 2024 (UTC)