Which is 12am and 12pm

Is it the night between Monday and Tuesday or between Tuesday and Wednesday? Some will say midnight is 12am, and therefore that midday or noon is 12pm.

When we talk about midnight last night or midnight tonight, the meaning is clear ; but less so when we talk about, for example, midnight on Sunday.

Is that at the beginning or at the end of Sunday?! The last bus arrives just before midnight on Friday nights. In English, do we use the hour clock or hour clock? In other words, do we say for example 2pm or ? In general conversations and situations in English, we use the hour clock format. In practice, that means counting the hours from 1 to 12 in the morning and in the afternoon. Sometimes, such sentences can be unclear : His plane leaves at Is that am or pm?

Planes leave at both those times. They sleep at night. What time is it? The current atomic clock system at NPL is the basis of all UK time, and cutting-edge research is being carried out to improve timekeeping accuracy even further. Learn more about our research on time. Learn more about our time services. Our research and measurement solutions support innovation and product development. We work with companies to deliver business advantage and commercial success.

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Analytics cookies We utilise Google Analytics cookies to help us to improve our website by collecting information on how it's used. Hence, if we refer to the mornings and say 1 am to 11 am, then 12 must follow as 12 am midday ; and, if we refer to the afternoons and nights and say 1 pm to 11 pm, then 12 must follow as 12 pm midnight. Think of it as simple counting.

Thank you for all your comments. It is indeed a complicated question. Midnight on Sunday is during the night between Sunday and Monday, as Joe says. With the hour clock, we start again from after For example after we do have ; ….. Same way after noon i. What do you think Mr. I agree with others who reason that 12 AM is midnight, as AM is one minute past midnight. Just as AM is one second past midnight. The 24 hour clock makes this more obvious and clear. My covid 19 shot is at March 23 at 12PM, logically that is 12 noon, but this is not a question of logic, but of time standards.

Midnight on Sunday is confusing.