24-hour clock

Timekeeping convention

24-hour clock12-hour clock
00:0012.00 a.m. - midnight
01:001:00 a.m.
02:002:00 a.m.
03:003:00 a.m.
04:004:00 a.m.
05:005:00 a.m.
06:006:00 a.m.
07:007:00 a.m.
08:008:00 a.m.
09:009:00 a.m.
10:0010:00 a.m.
11:0011:00 a.m.
12:0012:00 p. m. - noon[1]
13:001:00 p.m.
14:002:00 p.m.
15:003:00 p.m.
16:004:00 p.m.
17:005:00 p.m.
18:006:00 p.m.
19:007:00 p.m.
20:008:00 p.m.
21:009:00 p.m.
22:0010:00 p.m.
23:0011:00 p.m.
24:0012:00 a.m. - midnight

The 24-hour clock is a way of telling the time in which the day runs from midnight to midnight and is divided into 24 hours, numbered from 0 to 23. It does not use a.m. or p.m. This system is also referred to (only in the United States and the English speaking parts of Canada) as military time[1] or (only in the United Kingdom and now very rarely) as continental time. In some parts of the world, it is called railway time. Also, the international standard notation of time (ISO 8601) is based on this format.

World map showing the usage of 12 or 24-hour clock in different countries
  24-hour
  24-hour (12-hour orally)
  Both in common use
  12-hour

A time in the 24-hour clock is written in the form hours:minutes (for example, 01:23), or hours:minutes:seconds (01:23:45). Numbers under 10 have a zero in front (called a leading zero); e.g. 09:07. Under the 24-hour clock system, the day begins at midnight, 00:00, and the last minute of the day begins at 23:59 and ends at 24:00, which is identical to 00:00 of the following day. 12:00 can only be noon (midday). Midnight is called 24:00 and is used to mean the end of the day and 00:00 is used to mean the beginning of the day. For example, you would say "Tuesday at 24:00" and "Wednesday at 00:00" to mean exactly the same time.However, the U.S. military prefers not to say 24:00 - they do not like to have two names for the same thing, so they always say "23:59", which is one minute before midnight.

A 24-hour clock face

24-hour clock time is used in computers, by the militaries, for public safety, and in transport. In many African, Asian, European and Latin American countries people use it to write the time. Many people use it in speaking.

Many digital wristwatches and clocks can display the time of day using the 24-hour clock.

In railway timetables 24:00 means the end of the day. For example, a train due to arrive at a station during the last minute of a day arrives at 24:00; but trains which depart during the first minute of the day go at 00:00.

To write shop opening hours until midnight use, for example, "00:00–24:00", "07:00–24:00".

Advantages over the 12-hour clock system:

  • Fewer confusions between morning and evening; e.g. 7 o'clock in the evening is called 19:00.
  • People do not have to figure out if noon is 00h00, 24h or 12h to calculate duration.

Referenceschange

  1. 1.0 1.1 "How To Convert Military Time". lcym.org. Retrieved 2021-05-07.
🔥 Top keywords: Main Page2024Special:Search0Slash (punctuation)BlackFarrah BrittanySpecial:RecentChanges4 (number)Baike: AboutHelp:ContentsPeriodic tableXXXTentacionHelp:IntroductionFile:Sexual intercourse with internal ejaculation.webmDavidColourSOLID (object-oriented design)Adolf Hitler Uunona20 (number)6 (number)Baltimore24-hour clockBismillahir Rahmanir RaheemKrishnachandra RoyUnited StatesAli MalikovAlexia UmanskyMauricio Umansky2023Prophets of IslamSophia UmanskyBaike: Simple talkBaike: Contact usCristiano RonaldoBaike: Simple startThe Hunger Games: The Ballad of Songbirds & SnakesEnglish languageKaylee HottlePortia UmanskyBuying Beverly HillsR. Budd DwyerBrandon ScottList of people who have walked on the MoonList of U.S. states and territories by time zone50 (number)List of U.S. states by date of admission to the UnionGrassFast XSpecial:MyTalkThe Valley (2024 TV series)File:ASCII-Table-wide.svg2 Girls 1 CupProvinces and territories of CanadaModule:Unicode data/scriptsFrancis Scott Key Bridge (Baltimore)EasterAndrew TateSean CombsBaike: General disclaimerList of countries by areaTeenagerNicole ShanahanShah Rukh KhanList of mathematical symbolsList of fruitsGodzilla vs. KongThe Dark Knight TrilogySpecial:MyContributionsList of cities in MexicoTransformers: Rise of the BeastsLionel MessiList of countriesFile:Standing sexual intercourse.webmTalk:Main PageList of European countriesEnvironmentList of Premier League hat-tricksLes FerdinandNoli de CastroKyle RichardsNarendra ModiList of U.S. statesHelp:Authority controlList of countries by continentsSpider-man: across the spider-verseList of cities in FranceList of U.S. state capitalsGolden EdgeModule:CoordinatesWe the People PartyStrawberryList of vegetablesColon (punctuation)Murder of Junko FurutaShemaleCaféList of current members of the United States SenateBassirou Diomaye Faye