When emphasizing an exact or precise time, the abbreviations “a.m.” and “p.m.” are used. These two abbreviations stand for the Latin terms “ante meridiem” and “post meridiem,” which literally mean before noon and after noon. There are a few generally accepted ways to write these abbreviations in your writing.

Ante meridiem is commonly denoted as AM, am, a.m., or A.M.; post meridiem is usually abbreviated PM, pm, p.m., or P.M. Like many other sources, timeanddate.com uses “am” and “pm” when using the 12-hour format, but the other variants are equally correct and widely used.

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 1 or 0 to 24 or 23. It does not use a.m. or p.m.

24-Hour Time Format. Many places in the world use the 24-hour time format. 24-hour time format is similar regular AM/PM time, except that you keep counting up after you get past 12 PM (noon). So 1 PM in 24-hour format is 13:00, 2 PM is 14:00, and so on. All you need to do is add 12 to any time in the PM to get 24-hour format time.

2021年2月3日 · Follow these generally accepted guidelines to use a.m. and p.m. (or AM and PM) correctly in formal writing: Use the abbreviations a.m. and p.m. to indicate exact time. Use a.m. to refer to a time of day before noon, and p.m. to speak of a time between noon and midnight.

The number 12 is paired either with a 00 or a 24, while the numbers 1 through 11 are paired with the numbers 13 through 23, respectively. This modification allows the clock to also be read in 24-hour notation .

2023年12月22日 · The proper format for time is lower case with periods. It also explains that a.m. is ante meridiem, “before noon” and p.m. is post meridiem, “after noon”. This makes sense as to why the periods are necessary, though I don’t know how consistent it is across all Latin translations like that.

Enter your time 12-hour time format on the respective fields marked by labels. Make sure to choose the correct meridiem, is it AM or PM? Choose the exact time. Let's say you want to convert 4:30PM to 24-hour format. Enter 24 on hours, 30 on minutes and PM on meridiem, but it's already a default so let's move forward. Step 3

AP Style time of day holds that the time descriptors “ante meridiem” (before noon) and “post meridiem” (after noon) should be abbreviated with lowercase letters and with periods (a.m. and p.m.). AP warns against redundancies in your writing such as“10 a.m. this morning.” For instance, Wrong: We have breakfast planned for 10 a.m. Monday morning.

2024年7月19日 · AM and PM are abbreviations used in the 12-hour clock system to denote the two halves of a day. AM stands for “Ante Meridiem,” which is Latin for “before midday.” This term covers the hours from midnight to noon. On the other hand, PM stands for “Post Meridiem,” translating to “after midday,” and it includes the hours from noon to midnight.