# People who use military (24 hour) time... **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [October 28, 2017, 4:51pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082 "2017-10-28T16:51:24Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Dancer\_Flight](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dancer_flight/32/7601_2.png) [@Dancer\_Flight](https://boards.straightdope.com/u/Dancer_Flight)\ **Post date:** [October 29, 2017, 3:50am UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/41 "2017-10-29T03:50:33Z")
I adopted to the 24 hour clock when I was an astronomy grad student. When we didn’t have set classes my sleep schedule went totally wacky. 7:00am & 7:00pm look remarkable similar at times of the year, and if you are sleeping in an unfamiliar place and have just put in an 18 - 20 hour day of coding, the only clue you might have as to the actual time is if you have to do math when you look at the clock face. I also find it helps when setting alarms. Generally I don’t have to set a wake up for 18:00 but it can be easy to miss the dot (and does that mean AM or PM?) or the tiny text and inadvertently mis-set for the wrong half of the day. At a recent hotel stay I pretty much ignored the hotel alarm clock (I use my iPod for an alarm) but I noticed that it was running about 15 minutes fast. On the third day of my stay I looked closer and it was actually 12h15 fast (or 11h45 slow). The final reason I do 24 hour time is it is a lot easier to calculate durations across the noon boundary. At a recent job I was working from 7:00am to 5:30pm with an hour lunch break. 17.5 - 7 - 1 = 9.5 is an easier calculation. -DF ---
**Author:** ![Gatopescado](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gatopescado/32/5711_2.png) [@Gatopescado](https://boards.straightdope.com/u/Gatopescado)\ **Post date:** [October 29, 2017, 4:14am UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/42 "2017-10-29T04:14:23Z")
_The sun is the same in a relative way, but you’re older And shorter of breath and one day closer to death_ ---
**Author:** ![Desert\_Nomad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/desert_nomad/32/177_2.png) [@Desert\_Nomad](https://boards.straightdope.com/u/Desert_Nomad)\ **Post date:** [October 29, 2017, 6:37am UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/43 "2017-10-29T06:37:48Z")
> [@Crafter\_Man](#): > > This is too lame and petty for The Pit, so I am putting it here. > > I got an email at work yesterday that said, “The meeting will start at 1500.” > > Why do some people do this? All of my clocks - the clock on my phone, the clock on my computer, the clock in my car, the clocks at home - use AM/PM. When someone gives me a time like “1300,” “1700,” etc. I have to mentally convert it to AM/PM. And then I have to do it two or three times to make sure I did it correctly. > > Unless you’re in the military, don’t do this! You’re driving people bonkers. Because 6.7 billion people on the planet do it this way. Everyone except Americans. I must be one of the few Americans who has never served in the military and who always uses a 24-hour clock. ---
**Author:** ![WildBlueYonder](https://avatars.discourse-cdn.com/v4/letter/w/ce7236/32.png) [@WildBlueYonder](https://boards.straightdope.com/u/WildBlueYonder)\ **Post date:** [October 29, 2017, 11:11am UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/44 "2017-10-29T11:11:59Z")
Must be associated with metrics, the US can never get on board!! :dubious::dubious: I use it on my phone but I’m going to check my computer…Using it reminds me of the good ole days of the US Army! 😕 ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 29, 2017, 11:27am UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/45 "2017-10-29T11:27:24Z")
> [@Dancer\_Flight](#): > > … > I also find it helps when setting alarms. Generally I don’t have to set a wake up for 18:00 but it can be easy to miss the dot (and does that mean AM or PM?) or the tiny text and inadvertently mis-set for the wrong half of the day. > > At a recent hotel stay I pretty much ignored the hotel alarm clock (I use my iPod for an alarm) but I noticed that it was running about 15 minutes fast. On the third day of my stay I looked closer and it was actually 12h15 fast (or 11h45 slow). > … I sleep in a \*lot \*of hotels. I never use their clock but for curiosity I try to note whether it’s set right or not. That’s part of my pre-bed ritual which includes the hard-learned step of checking to see if the alarm was left on by the last guest or maid. IME about 75% of them are set 10-15 minutes fast. I blame flight attendants. About 15% have the am/pm indicator wrong. 'Merkins be idjits. ---
**Author:** ![Mean\_Mr.Mustard](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mean_mr.mustard/32/3865_2.png) [@Mean\_Mr.Mustard](https://boards.straightdope.com/u/Mean_Mr.Mustard)\ **Post date:** [October 29, 2017, 11:38am UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/46 "2017-10-29T11:38:49Z")
> [@Crafter\_Man](#): > > [SIZE=“1”]Why do some people do this? All of my clocks - the clock on my phone, the clock on my computer, the clock in my car, the clocks at home - use AM/PM… **Crafter\_Man** , why did you wait so long to inform us of your clocks? So sorry, we didn’t know! -the rest of the world ---
**Author:** ![Enter\_the\_Flagon](https://avatars.discourse-cdn.com/v4/letter/e/b9bd4f/32.png) [@Enter\_the\_Flagon](https://boards.straightdope.com/u/Enter_the_Flagon)\ **Post date:** [October 29, 2017, 2:05pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/47 "2017-10-29T14:05:45Z")
The American film industry is another where you’ll sometimes see the 24-hour clock, since film crews operate during both day and night, depending on the needs of the project. A 7:00 “call time” is almost as likely to mean p.m. as a.m. When you use it frequently, it becomes second nature. I don’t mind it at all. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [October 29, 2017, 2:13pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/48 "2017-10-29T14:13:42Z")
> [@Mean\_Mr.Mustard](#): > > **Crafter\_Man** , why did you wait so long to inform us of your clocks? So sorry, we didn’t know! > > -the rest of the world Yes, I am genuinely shocked at the responses here. Guess I need to get with the times. 😉 ---
**Author:** ![Shinna\_Minna\_Ma](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@Shinna\_Minna\_Ma](https://boards.straightdope.com/u/Shinna_Minna_Ma)\ **Post date:** [October 29, 2017, 2:16pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/49 "2017-10-29T14:16:28Z")
> [@chappachula](#): > > Now here’s my question: > For those of us who do use the 24 hour clock …do you do so in speech, or only in writing? I live in Israel, and all times are written using 24 hours. All our bedroom clocks display 24 hour time, and all our wall timers have a 24 hour dial. It’s all written; nobody will refer to 3 p.m. as 15:00 when speaking. If someone asks me the time, I won’t answer “5 minutes after 21.” ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [October 29, 2017, 2:21pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/50 "2017-10-29T14:21:11Z")
> [@Crafter\_Man](#): > > Yes, I am genuinely shocked at the responses here. Guess I need to get with the times. 😉 For what it is worth, getting use to it should take all of 1-2 weeks tops if you want. Less with a CC/Drill Sgt type drilling it into your head. ---
**Author:** ![casdave](https://avatars.discourse-cdn.com/v4/letter/c/c6cbf5/32.png) [@casdave](https://boards.straightdope.com/u/casdave)\ **Post date:** [October 29, 2017, 3:22pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/51 "2017-10-29T15:22:09Z")
If you are working 24 hour shift patterns it is quite important to be unambiguously clear, and I imagine that if you live north of the Arctic circle when there is either no day, or no night then it probably is a good idea too ---
**Author:** ![JacobSwan](https://avatars.discourse-cdn.com/v4/letter/j/a6a055/32.png) [@JacobSwan](https://boards.straightdope.com/u/JacobSwan)\ **Post date:** [October 30, 2017, 11:20am UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/52 "2017-10-30T11:20:25Z")
> [@jtur88](#): > > It doesn’t matter. I still don’t know whether 00:00 today’s date was last night, or tonight. The same as I don’t know whether 12:00 pm is noon or midnight. > > It’s 2017, folks. How come out modern technological civilization can’t figure out a way to express what time it is? 12:00am will get you 50% of the population thinking it’s noon and the same amount thinking it’s midnight. In a similar vein, is next tuesday tomorrow? or a week tomorrow? Same kind of distribution. ---
**Author:** ![Scougs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/scougs/32/3158_2.png) [@Scougs](https://boards.straightdope.com/u/Scougs)\ **Post date:** [October 30, 2017, 12:43pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/53 "2017-10-30T12:43:42Z")
UK person here. Written time is pretty much always 24 hour. Four digits cleanly and clearly convey all the information you need. (With the possible exception of potential ambiguity of 0000). Have a look at this bus timetable between Edinburgh and Glasgow. [Citylink Bus Timetable.](http://www.citylink.co.uk/timetables/Winter2017/900-sep17.pdf) Dead simple, and helpfully uses 2359 as a departure time to make it really clear.🙂 Compare that with a US timetable. [Amtrak Northeast Corridor](https://www.amtrak.com/content/dam/projects/dotcom/english/public/documents/timetables/Northeast-Schedule-W02-090517.pdf) All those unncessary As and Ps cluttering the place up. I get that it’s what you’re used to. Like cups and spoons rather than grams, or putting the month first. Weirdos. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [October 30, 2017, 1:07pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/54 "2017-10-30T13:07:42Z")
24:00 30 Oct is the same moment as 00:00 31 Oct, depending on whether you want to count it as part of the preceding day or the following one. So the 24-hour clock has that one covered, too. The standard American timekeeping fails on that point, but not because of it being 12 hours, but because it doesn’t use zero. When it comes to dates, I always use the format 30 Oct 2017 (possibly dropping the year, if it’s unambiguous). This has a few advantages. For one, no matter what format my reader is used to, it’s never ambiguous, and they can always see what I mean. For another, the three letters in the middle serve as a separator between the numbers, so there’s no need for hyphens or slashes to separate them (and slashes, in messy handwriting, can be mistaken for ones). ---
**Author:** ![The\_Librarian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/the_librarian/32/402_2.png) [@The\_Librarian](https://boards.straightdope.com/u/The_Librarian)\ **Post date:** [October 30, 2017, 1:36pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/55 "2017-10-30T13:36:56Z")
I have to look up which part of the day is AM or PM. I hate that notation. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 30, 2017, 2:01pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/56 "2017-10-30T14:01:13Z")
> [@Scougs](#): > > Have a look at this bus timetable between Edinburgh and Glasgow. [Citylink Bus Timetable.](http://www.citylink.co.uk/timetables/Winter2017/900-sep17.pdf) Dead simple, and helpfully uses 2359 as a departure time to make it really clear.🙂 > … Our scheduling department makes sure that nothing is scheduled to arrive or depart at exactly 0000 local or 0000 UTC. An extra minute or several is added or subtracted as needed. Normally they greatly prefer to set the time at 2359 or earlier unless it will naturally fall after about 0015. > [@Chronos](#): > > 24:00 30 Oct is the same moment as 00:00 31 Oct, depending on whether you want to count it as part of the preceding day or the following one. So the 24-hour clock has that one covered, too. … It depends on which standard you use (ref [xkcd: Standards](https://xkcd.com/927/)) but IMO/IME 2400 is not well-defined in the standards I’ve used. Thoughtful people can decode it correctly, but strictly speaking it’s an invalid time expression. ---
**Author:** ![Isamu](https://avatars.discourse-cdn.com/v4/letter/i/7c8e57/32.png) [@Isamu](https://boards.straightdope.com/u/Isamu)\ **Post date:** [October 30, 2017, 2:06pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/57 "2017-10-30T14:06:12Z")
> [@Crafter\_Man](#): > > This is too lame and petty for The Pit, so I am putting it here. > > I got an email at work yesterday that said, “The meeting will start at 1500.” > > Why do some people do this? All of my clocks - the clock on my phone, the clock on my computer, the clock in my car, the clocks at home - use AM/PM. When someone gives me a time like “1300,” “1700,” etc. I have to mentally convert it to AM/PM. And then I have to do it two or three times to make sure I did it correctly. > > Unless you’re in the military, don’t do this! You’re driving people bonkers. It’s called 24 hour time. It’s better. ---
**Author:** ![Morgenstern](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@Morgenstern](https://boards.straightdope.com/u/Morgenstern)\ **Post date:** [October 30, 2017, 2:11pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/58 "2017-10-30T14:11:58Z")
> [@running\_coach](#): > > There’s certainly no confusing 12 noon with 12 midnight. Unless you live in one of those places where it’s light, or dark, three months a year. 🙂 ---
**Author:** ![DCnDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dcndc/32/2842_2.png) [@DCnDC](https://boards.straightdope.com/u/DCnDC)\ **Post date:** [October 30, 2017, 2:16pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/59 "2017-10-30T14:16:03Z")
> [@Buttercup\_Smith](#): > > I work for the military and it’s become habit. I also work for the military, and in medicine, so it’s not only habit, it’s expected. I’m working in their world, I have to speak the native language. I don’t do it outside of work, not intentionally at least, to people who are unrelated to either field. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [October 30, 2017, 2:26pm UTC](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082/60 "2017-10-30T14:26:16Z")
A partial look at something I look at every work day. For me the times are second nature. I don’t have to think about it at all. I would think most business programmers use 24 hr time. I’m sure most science programmers do. ```auto **Name Description Time** FRIDAY Cust Ship Rpt for QC 05:15 SUNDAY Sunday Post IPL of AS4 05:00 SUNDAY2 Sunday Rebuild Co19 05:10 UNLOAD Unload Tape 0430 Morning Job Stream 04:30 0500WD Morning Jobs Weeks Day 05:00 EOUTQ Clears Outqs for set d 05:20 SIDWNLD IDSI Download from AS4 20:00 0QTYCL Invoices Wth 0 Qty Bil 16:30 AUDIT IT Audit Reports 02:00 AUPDDATE Update LDA's for ROBOT 00:01 MSUPCL Update KC files w/ LIM 10:20 ``` [Previous page](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082.md?page=2) [Next page](https://boards.straightdope.com/t/people-who-use-military-24-hour-time/800082.md?page=4)