1595: 30 Days Hath September

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30 Days Hath September
There's a cool mental calculation hack I recently learned for this: If you open the calendar app on your phone or computer, the highest-numbered box along the bottom is equal to the number of days in the month!
Title text: There's a cool mental calculation hack I recently learned for this: If you open the calendar app on your phone or computer, the highest-numbered box along the bottom is equal to the number of days in the month!


Thirty days hath September is a mnemonic frequently used to remember how many days each month has in the Gregorian calendar. Cueball is reciting the mnemonic trying to figure out how many days October has. This comic was released during the last week of October (the 26th) where it becomes increasingly relevant to know if there are 30 or 31 days in the month. However, he seems unable to concentrate on reciting the poem correctly, keeping track of which months the poem has named and keeping in mind the specific month he was interested in, so by the time he finishes the poem he is unsure whether October was in the list of 30-day months or not. So he starts over again with the same result every single time, as can be seen from the caption below the frame. It seems he also get stuck in all the other months disregarding if it is one of the month mentioned in the mnemonic.

There are numerous versions of the mnemonic, some of which rhyme better, but this version is one of the more common ones. The knuckle mnemonic is an unrelated alternative.

In the caption, Randall states that this happens to him every month. It's assumed that, after a number of iterations with the poem, he eventually remembers the months correctly and figures out the number of days in the current month, which he then remembers until the month changes and forces him to resort to the mnemonic again.

The title text is a parody of life hacking, and suggests just looking up on one's computer's calendar how many days there are in each month, with the punchline disguised by over-explaining the process of the "cool mental calculation hack" (even though there's nothing even remotely resembling a mental calculation in checking a calendar). Alongside the comic, the joke is that the mnemonic is supposed to be the real "cool mental calculation hack" which supposedly saves a lot of effort. This is similar to 1567: Kitchen Tips.

It may also be considered amusing that Cueball is unsure whether there are 31 days in October, seeing as Halloween is a largely celebrated holiday on the 31st.


[Cueball is thinking.]
Cueball: Thirty days hath September, April, June and November
Cueball: All the rest have 31—except February, which has 28, and leap year makes it 29.
Cueball: Wait, which month was I listening for? Oh right, October.
Cueball: Did I say "October" in there? Now I can't remember.
Cueball: 30 days hath September...
I get stuck in this loop every month.

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THIS RHYME IS TERRIBLE. You can slot the months into it in nearly any order and it will still scan. The knuckle trick is far superior. https://en.wikipedia.org/wiki/Thirty_days_hath_September#Knuckle_Mnemonic CLAVDIVS (talk) 06:00, 26 October 2015 (UTC)

I use the knuckle trick too. And I am Dutch, so not only the "German, French, Swiss, Romanians and Belgians" use that trick. I count from the index finger and reverse on the little finger for July and August. Might not be representative for all Dutch, I've heard the rhyme too. (suitably translated) -- 09:36, 26 October 2015 (UTC)
I'm floored by the claim that the 'knuckle trick' is mostly used in Europe. I learned it from my grandmother, who never lived outside the state of Texas in over 90 years, and she was a third-generation American, ultimately of Irish/Scottish/Welsh descent. 12:00, 28 October 2015 (UTC)
From Jan to Jul(1~7) its odd numbers 31 days, while from Aug to Dec(8~12) its even numbers 31. Feb is 28 or 29. Much shorter. - MythSearcher (talk) (please sign your comments with ~~~~)
Or (in other words) subtract 7 if number of month is above 7. Then odd always means 31 and even 30 or February. Sebastian -- 07:39, 26 October 2015 (UTC)
Or, in yet other words, if (number of month) mod 7 is odd. But the knuckle trick is so much easier to teach to young children... 08:34, 3 November 2015 (UTC)
As above, except that I use Hallowe'en and New Year as checks! (talk) (please sign your comments with ~~~~)
I come from the UK. I have never heard the rhyme and everyone I know uses the knuckle trick. Though London is not exactly representative of the whole country... 09:51, 26 October 2015 (UTC)
I've been taught the knuckle mnemonic as a child; it went index finger to little finger, then to other hand starting from index finger again. Incidentally, I'm Russian (as opposed to German, French, Swiss, Romanian, Belgian, or Dutch). -- 10:00, 26 October 2015 (UTC)

Datum point: British, was taught the rhyme ('alone'-rhyming version) when young but then learnt the (apparently widespread) 'knuckle-trick' from I-don't-know-where. Little-finger knuckle is January, index-finger knuckle is July, then right-hand in reverse, for me, until out of months... So I tend to use the latter more, now. 17:23, 26 October 2015 (UTC)

I'm American and I also recall hearing the finger trick in school. I don't recall which ones I used though. At some point I just remembered that they alternate long/short but July and August are both long (I think my dad telling me the story of how Julius Caesar and Caesar Agustus both wanted a long month named after them was the reason) and just counted mentally, and at this point I just have each one memorized that way. -- 05:28, 28 October 2015 (UTC)

I always heard "30 days hath september, april june and november, all the rest have 31, except february alone. And that has 28 days clear, with 29 in each leap year." How do people remember it if it doesn't rhyme?- madness! (talk) (please sign your comments with ~~~~)

Personally I could swear I heard "except for February which has none" as a child, and recall thinking as a child that made no sense. However, literally none of the other variants work- "alone" doesn't rhyme with "one" (...even though they should; are there any accents that pronounce those the same?), and it also doesn't scan; this comic actually sent me to Wikipedia to look; turns out they have a massive list of variants but the lack of rhyming there is painful. The only ones that work are those that give up on describing February (ex. "Except for February—and that's no fun!"). I strongly suspect based on the lack of rhyming that the rhyme originated with something like "which has none" and was modified to make sense at the expense of rhyming. -- 05:28, 28 October 2015 (UTC)
While, in my normal inflection of speech, "wonn" certainly doesn't rhyme with "al-own", I find it quite easy to go for a nearly-but-not-quite rhyme by extnding the first and shortening the second. There's worse 'rhymes' out there. Traditional local accents also vary a lot in my area, between towns a few mere miles apart (e.g. "book" => "buk" or "bewk") and I'm sure I could find some old person who still spoke a pure enough form of their own local dialect to effortlessly pull this trick off, without even trying, even if it doesn't match in the modern 'smeared-English'. 14:07, 28 October 2015 (UTC)
No no no, its "30 days hath November, August, March and December..." --Pudder (talk) 11:31, 26 October 2015 (UTC)
Pudder, No no no no no no, March and August and December have 31 days! 23:30, 27 October 2015 (UTC)
"Twenty days have October,
January, March and July.
Also June, May, November,
February, August and April.
Also also December and September,
But they also have.
Between eight and eleven additional days for which this mnemonic is insufficiently detailed about;
Nor does it even rhyme or scan and its punction is! Terrible?"
HTH, HAND. 14:37, 21 February 2024 (UTC)

In Spain both rhyme and knuckle are well-known, and usually taught to children (the rhyme suitably translated, of course). For some reason, I've always found it easier to just remember the number of days by memory than resorting to any mnemonic trick. I tend to use the known numbers to check if I remember the mnemonic correctly, and not vice versa. Also, it's usual to see people wondering which number corresponds to which month (e.g. October is month 10), which I also remember no problem since I have memory. Jojonete (talk) 12:37, 26 October 2015 (UTC)

Of course if we hadn't moved the start of the year from March to January, September, October, November and December would make much more sense as months 7, 8, 9 and 10! 15:30, 26 October 2015 (UTC)
I'm from Denmark and here I have heard of the knuckle method, but we do not have a rhyme that is so well know that I have heard of it (but I'm sure someone has.) But as the Jojonete wrote I also just know which month have how many days by memory etc. But I have told my six year old daughter about the knuckle method. I think it is great that it works. And everyone knows that February is the one with 28 days, so that is not the difficult part to remember... --Kynde (talk) 13:50, 26 October 2015 (UTC)

I tried the mouseover text trick and got "7" for October. Someone help! 17:10, 26 October 2015 (UTC)

You are very funny. The mouseover text trick works great when your app is set to "month" view, but fails if set to "week" view. 23:30, 27 October 2015 (UTC)

October of all months seems like a pretty easy one to keep track of, simply because October 31st is a pretty popular holiday. 18:48, 26 October 2015 (UTC)

A holiday where? Why would it be a holiday? 03:00, 28 October 2015 (UTC)
brain adaptation ridicule…celebration 09:44, 27 October 2015 (UTC) me thinks that while the absurdity of these life hacks has been explained well the deeper issue might yet be missed here: the cultural shift from relying on mental recall and concentration to adapting your brain to rely on technology more than before, reduced attention span and reduced factual memory (better childhood telephone number recall than children's mobile numbers recall) and optimized lookup routines (talk) (please sign your comments with ~~~~)

digital amnesia! -- 10:02, 27 October 2015 (UTC)

http://www.bbc.com/news/education-34454264 -- 10:38, 27 October 2015 (UTC)

+ http://www.business2community.com/brandviews/wyzowl/its-official-we-have-shorter-attention-spans-than-goldfish-infographic-01353885#w1RCPWdWy1LoDlvI.97 -- 10:48, 27 October 2015 (UTC)

My uncle had a nonsense rhyme based on this:
Thirty days hath September,
April, June, and no wonder
All the rest ate peanut butter,
Except Grandma, who rode a tricycle
about this color. (holds hand 3 feet above ground) 13:19, 27 October 2015 (UTC)

Yay! I came here specifically to post this version, but was beaten to it. It's from the Napolean XIV album from 1966: https://www.youtube.com/watch?v=kvABMymQz_k (talk) (please sign your comments with ~~~~)

pianomonths.png --Zom-B (talk) 08:09, 30 October 2015 (UTC)

Actually you just have to remeber August. Start with January, 31 days. Now it alternates between less-than 31 days and 31 days until July. August does not fit in with 31 days. Start alternating again until december. 14:38, 2 November 2015 (UTC)

Alternate calendar system that would make remembering month lengths easier:

Jan 31 Feb 30 Mar 31 Apr 30 May 31 Jun 30 Jul 31 Aug 30 Sep 31 Oct 30 Nov 30/leap year 31 Dec 30

To convert back to Gregorian calendar: Jan 1 - Feb 28 same as Gregorian. Feb 29 - Aug 30 add two to the day to get back to the Gregorian calendar. Sep 1 - Dec 30 add one to the day

Please correct the conversion factors if they are incorrect!