# Do any English-speaking nation-states use 24-hour time? **URL:** \ **Category:** Factual Questions\ **Created:** [October 8, 2003, 7:04pm UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337 "2003-10-08T19:04:22Z")\ **Posts on this page:** 14\ **Page:** 2
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [October 9, 2003, 4:29pm UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/21 "2003-10-09T16:29:47Z")
\ Hey, **Spoons** , how’d the move go? \ Long-distance buses and regional trains around Toronto use the 24-hour clock as well… I think that’s standard for scheduled transportation, and not a Quebec thing at all. ---
**Author:** ![Acsenray](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/acsenray/32/4519_2.png) [@Acsenray](https://boards.straightdope.com/u/Acsenray)\ **Post date:** [October 9, 2003, 4:36pm UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/22 "2003-10-09T16:36:14Z")
Well, **Abby** , the example you give is, to me, an example of a use within a specialised field. So people involved in the theatre profession use the 24-hour clock for task-related purposes. It’s a kind of jargon. The theatre industry _doesn’t_ use it when communicating showtimes to the public. So it’s a specialised use, not a general one. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [October 9, 2003, 4:48pm UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/23 "2003-10-09T16:48:00Z")
More thoughts… The TTC (local buses, trains, streetcars in Toronto) uses AM and PM in their posted schedules at bus stops. **Derleth** , why drop the colon? (Yes, I know many people do.) To me, the colon provides the very significant indication that 18:00 (your “eighteen hundred”) is _not_ a simple base-ten number. Simply writing “1800” implies that the previous number was “1799”, not “1759”. And the military use of the “hundred” expression amplifies this. ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [October 9, 2003, 7:19pm UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/24 "2003-10-09T19:19:45Z")
I drop the colon because I always zero-pad the number so it’s four digits. Then I can mentally scan the first two numbers to get hour and the last two to get minute. Under that system, the colon is simply visual clutter. So, 8:00 AM becomes 0800, which I can read immediately as oh-eight-hundred. It’s all very automatic. Finally, those using the 12-hour clock tend to keep the colon in place. So I can possibly tell the difference between someone who uses 12-hour and someone who uses (my version of) 24-hour simply by noting who’s using colons. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [October 9, 2003, 9:16pm UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/25 "2003-10-09T21:16:08Z")
> [@](#): > > \*Originally posted by acsenray \* > \*\*Oh and, by the way, 12 p.m. is noon and 12 a.m. is midnight. I’ve recently discovered (to my surprise) that there seem to be a lot of people who don’t understand this. \*\* There’s 12 noon and 12 midnight. There are no such times as 12:00 am and 12:00 pm. The problem is that most modern ways of handling time require that an am or pm be added. Then the question becomes, what convention should be used to assign them? A case can be made either way. Logically, if you progress from 11:59 pm to 12:00, that should be 12:00 pm. But just as logically, if you progress from 12 to 12:01 am, that should be 12:00 am. The same for times approaching noon. The usual practice is indeed to assign am to 12 midnight and pm to 12 noon, but there is nothing automatic or indisputable about doing so. And there should be no surprise that people have to think about the convention or sometimes get it wrong. Conventions are arbitrary, pretty much by definition. ---
**Author:** ![Acsenray](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/acsenray/32/4519_2.png) [@Acsenray](https://boards.straightdope.com/u/Acsenray)\ **Post date:** [October 9, 2003, 9:37pm UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/26 "2003-10-09T21:37:02Z")
Of course it’s arbitrary. Almost everything about human language is arbitrary. “12 p.m.” is arbitrarily assigned to noon in the same way that “twelve” is arbitrarily assigned to “11 + 1.” But this – > [@](#): > > There’s 12 noon and 12 midnight. There are no such times as 12:00 am and 12:00 pm. – is patently false. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [October 10, 2003, 12:14am UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/27 "2003-10-10T00:14:16Z")
[National Institute of Standards and Technology](http://www.boulder.nist.gov/timefreq/general/misc.htm) > [@](#): > > Are noon and midnight 12 a.m. or 12 p.m.? > > This is a tricky question. The answer is that the terms 12 a.m. and 12 p.m. are wrong and should not be used. > > To illustrate this, consider that “a.m” and “p.m.” are abbreviations for “ante meridiem” and “post meridiem.” They mean “before noon” and “after noon,” respectively. Noon is neither before or after noon; it is simply noon. Therefore, neither the “a.m.” nor “p.m.” designation is correct. [MadSci Network: Astronomy](http://www.madsci.org/posts/archives/mar2001/984016709.As.r.html) > [@](#): > > Re: Is 00:00 hours (midnight) 12:00 AM or 12:00 PM ? > Date: Tue Mar 6 17:08:13 2001 > Posted By: Steven Furlanetto, Grad student, Astronomy, Harvard-Smithsonian Center for Astrophysics > Area of science: Astronomy > > That’s a good question! In everyday use, midnight is normally denoted as 12:00 AM. However, if you want to be technical, midnight and noon are neither AM or PM. This is because `AM' means `ante meridian,’ or before noon, while `PM' means `post meridian,’ or after noon. So by definition, noon itself can’t be in either piece, and similarly with midnight. [Royal Observatory Greenwich](http://www.nmm.ac.uk/site/request/setTemplate:singlecontent/contentTypeA/conFaq/contentId/78) > [@](#): > > Q. Is noon 12 a.m. or 12 p.m.? (Anon) > > 12 noon is neither a.m. nor p.m. > > To avoid confusion, the correct designation for twelve o’clock is 12 noon or 12 midnight. Alternatively, the twenty-four-hour-clock system may be used. [Words and Expressions](http://sir.free.fr/words2.htm) > [@](#): > > Are noon and midnight 12 a.m. or 12 p.m.? > > Answer: > > This is perhaps the trickiest time question of them all. The answer is that the terms 12 a.m. and 12 p.m. are wrong and should not be used. > > To illustrate this, consider that “a.m” and “p.m.” are abbreviations for “ante meridiem” and “post meridiem.” They mean “before noon” and “after noon,” respectively. Noon is neither before or after noon; it is simply noon. Therefore, neither the “a.m.” nor “p.m.” designation is correct. On the other hand, midnight is both 12 hours before noon and 12 hours after noon. Therefore, either 12 a.m. or 12 p.m. could work as a designation for midnight, but both would be ambiguous. > > To get around the problem, the terms 12 noon and 12 midnight should be used instead of 12 a.m. and 12 p.m. I guess we’re all surprised at things other people don’t know. But that’s why there’s an SDMB. ---
**Author:** ![Apollon](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Apollon](https://boards.straightdope.com/u/Apollon)\ **Post date:** [October 10, 2003, 1:48am UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/28 "2003-10-10T01:48:30Z")
> [@](#): > > \*Originally posted by MartinL \* > \*\*Actually, we speak German in Austria, and I think that **Apollon** just wanted to say that we do use all numbers from 0 (zero) to 23 in addition with the German equivalent of _o’clock_ (_Uhr_) when talking about time, although there is also a more old-fashioned way that’s like using AM and PM in English. > And yes, by this analogy, we do say _zero o’clock_ when we refer to times between 0:00 and 0:59. \*\* Exactly. 🙂 BTW, “twenty-four o’clock” is at least as common as “zero o’clock”, though you can use it only to describe that precise point of time. There is no “twenty-four and thirty”, only “zero and thirty”. Perhaps the idea is that midnight is the point where the previous and the next day meet. ---
**Author:** ![biqu](https://avatars.discourse-cdn.com/v4/letter/b/7feea3/32.png) [@biqu](https://boards.straightdope.com/u/biqu)\ **Post date:** [October 10, 2003, 2:15am UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/29 "2003-10-10T02:15:42Z")
> [@](#): > > _Originally posted by Sunspace_ > “Eighteen o’clock” seems perfectly logical to me. I would have a few issues with “twenty-five o’clock” though… I worked a late-night shift at an on-campus job at my undergraduate institution. I would finish at 1 a.m., but on my timesheet I wrote all my hours on the day I started work. For this reason I signed out at 25:00 rather than 01:00, since I didn’t want my hours distributed across two days. If I worked Wednesday night and the pay period ended on Wednesday, to be technically accurate I would have had to put the first hour of Thursday on the timesheet of the next pay period, which would mean that one hour’s pay would have to wait until the next pay period to be dispensed. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [October 10, 2003, 2:49am UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/30 "2003-10-10T02:49:12Z")
I just _knew_ that someone somewhere would actually come up with a coherent use for “25:00”… 🙂 ---
**Author:** ![Morelin](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Morelin](https://boards.straightdope.com/u/Morelin)\ **Post date:** [October 10, 2003, 5:32am UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/31 "2003-10-10T05:32:36Z")
As I recall 12 midnight was 2400, and then it switched to 0001. ---
**Author:** ![MartinL](https://avatars.discourse-cdn.com/v4/letter/m/ebca7d/32.png) [@MartinL](https://boards.straightdope.com/u/MartinL)\ **Post date:** [October 10, 2003, 6:22am UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/32 "2003-10-10T06:22:48Z")
> [@](#): > > \*Originally posted by amore ac studio \* > \*\*I worked a late-night shift at an on-campus job at my undergraduate institution. I would finish at 1 a.m., but on my timesheet I wrote all my hours on the day I started work. For this reason I signed out at 25:00 rather than 01:00, since I didn’t want my hours distributed across two days. If I worked Wednesday night and the pay period ended on Wednesday, to be technically accurate I would have had to put the first hour of Thursday on the timesheet of the next pay period, which would mean that one hour’s pay would have to wait until the next pay period to be dispensed. \*\* I have read things like “25:00” on protocols, for example. When some rules demand that a decision must be made until a certain date, there are two common tricks to archieve this despite failure to do so (Is this called an oxymoron?): They stop the watch in the meeting room at about one minute before midnight and all subsequent events are protocolled with 23:59. This strategy could mess up with the order of events. They do not switch to 00:00 at midnight, but rather continue counting (24:00, 25:00, …) and keep assigning the date of the previous day to events. On review, I think this is not much different from what **amore ac studio** described. ---
**Author:** ![clairobscur](https://avatars.discourse-cdn.com/v4/letter/c/839c29/32.png) [@clairobscur](https://boards.straightdope.com/u/clairobscur)\ **Post date:** [October 10, 2003, 9:50am UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/33 "2003-10-10T09:50:19Z")
> [@](#): > > \*Originally posted by Achernar \* > \*\*And if so, how do they pronounce it? > > I want to know how I’m supposed to say the time 18:00 in English. I know in French it’s “_dix-huit heures_” (eighteen hours), \*\* Actually, in french, both are used : one can say “il est 18 heures” (“it’s eighteen hours”, litterally) or “il est 6 heures” (“it’s six hours” still literally), possibly adding “de l’apres-midi” or “du soir” (“in the afternoon” or “in the evening”) if needed. However, it seems to me that “il est 18 heures” tends to become slightly more common. ---
**Author:** ![Acsenray](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/acsenray/32/4519_2.png) [@Acsenray](https://boards.straightdope.com/u/Acsenray)\ **Post date:** [October 10, 2003, 12:22pm UTC](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337/34 "2003-10-10T12:22:06Z")
The NIST quotes are interesting, but it’s an appeal to authority that is clearly overwhelmed by reality, including a number of other authorities, such as style guides. They do nothing to support the statement that “There are no such times as 12:00 am and 12:00 pm,” a statement that, as I said before, is patently false. Language, particularly American English, is not defined by authority. [Previous page](https://boards.straightdope.com/t/do-any-english-speaking-nation-states-use-24-hour-time/206337.md?page=1)